DIY Treasure Chest for Pirate Trunk or Treat Decor

DIY, Halloween, Holidays

Published October 29, 2026

This DIY treasure chest started as a pile of old cardboard boxes and a few sheets of craft foam, and it ended up being the star of our church trunk or treat. We went full pirate this year, costumes and all, so the van needed a treasure chest worthy of the whole crew.

It looks like a real wooden chest with aged gold hardware, but it’s really just cardboard, craft foam, hot glue, and a little paint. The kids got in on the action too, which made it even more fun.

DIY treasure chest with a weathered dark wood finish sitting open in a van’s cargo area, filled with gold coins, colorful gems, and pearl strands, while a skeleton peeks over the lid and a phone streams a football game from the liftgate above a pirate trunk or treat setup.

And yes, that’s a phone propped up on the liftgate. We had the BYU game playing the whole time so we could keep one eye on the score between handing out treats. Priorities, people.

DIY Treasure Chest: At a Glance

Here’s the whole process before we get into the step by step photos:

  1. Hot glue three equal cardboard rectangles into the bottom, front, and back
  2. Glue on the two side pieces from the inside
  3. Trace a mixing bowl to make two rounded lid sides
  4. Wrap the rounded sides in cardboard to form the curved lid
  5. Attach the lid with packing tape inside and out
  6. Cover everything in brown craft foam planks
  7. Frame the edges with black craft foam trim and a lock detail
  8. Spray the whole chest with red primer
  9. Paint the trim black and the planks brown
  10. Rub Antique Gold Rub ‘n Buff onto the trim
  11. Fill it with treasure

Quick Answer: How Do You Make a DIY Treasure Chest?

Build a box from cardboard, then make a curved lid by tracing a mixing bowl for the rounded sides and wrapping them in a cardboard sheet. Tape the lid on as a hinge, cover the chest in brown craft foam planks, and frame the edges with black foam strips. Prime it, paint the planks brown and the trim black, then rub Antique Gold Rub ‘n Buff over the trim so it looks like aged metal.

Supplies for a DIY Treasure Chest

Most of this you probably already have in the garage or craft closet. I used old shipping and moving boxes for the cardboard, so the base of the chest was free.

For the Chest

For Painting

Step 1: Build the Bottom, Front, and Back

Start with three rectangles of cardboard that are all the same size. These become the bottom, front, and back of your DIY treasure chest.

Lay them flat in a row and tape the seams with clear packing tape. The tape is just there to hold everything together temporarily while you work.

Crystel running clear packing tape along the seam between equal cardboard rectangles laid flat on a wood table, temporarily joining the bottom, front, and back pieces of a custom sized cardboard box.

Next, fold the front and back pieces up and use your hot glue gun to run a line of hot glue along each inside seam. This is what actually holds the box together, so don’t be shy with the glue.

Crystel folding up one side of the taped cardboard and running hot glue along the inside seam to start shaping a cardboard box, as a young helper watches from across the table.
Crystel holding the front and back cardboard panels upright while hot gluing the second inside seam to form the open base of a pirate treasure chest, with a young helper resting their head on the table behind it.

As you can see, my helpers were riveted by this part of the process.

Step 2: Add the Side Pieces

Cut two more pieces of cardboard for the sides of the DIY treasure chest. Hold each one in place against the front and back, then hot glue the seams from the inside.

Crystel holding a cardboard side panel in place against the front and back pieces of a custom-sized cardboard box base, lining up the edges before gluing, while a young helper rests their chin on the table behind it.
Crystel reaching into the cardboard box with a hot glue gun to seal the inside seam where the side panel meets the front of her cardboard treasure chest.

Now you’ve got an open cardboard box! Don’t worry about any printing or labels on the inside. Mine still says exactly which moving box it used to be, and nobody will ever know once it’s full of treasure.

Finished open cardboard box sitting on a wood table, with printing from a repurposed moving box visible on the inside panel and two young helpers peeking over the top.

Step 3: Make the Rounded Lid Sides

The curved lid is what makes it look like a real pirate treasure chest, and the secret tool is sitting in your kitchen cabinet. I grabbed a large stainless steel mixing bowl, flipped it upside down on a piece of cardboard, and traced around it. I cut along the traced line with my X-ACTO knife, then repeated the process on the second side.

Crystel tracing around an upside-down stainless steel mixing bowl on a piece of cardboard to draw the rounded shape for the side of a cardboard trunk lid.
Crystel holding the cardboard upright and cutting along the traced curved line with a blue utility knife to make a rounded side piece for a cardboard chest lid, as a young helper works at the table behind her.

The key here is size. Each rounded piece needs to be the same width as the side pieces of your box, so the lid of your DIY treasure chest ends up the same size as the base.

Step 4: Wrap the Lid in Cardboard

Cut a flat sheet of cardboard that’s the same width as the base of your DIY treasure chest. Hot glue the curved edge of one rounded piece along the end of the sheet.

Then slowly bend the cardboard over the curve, gluing as you go. Take your time so the curve stays smooth.

Crystel hot gluing the curved edge of a rounded cardboard side piece onto a flat sheet of cardboard cut to the width of the chest, as a young helper watches from across the table.
Crystel bending the flat cardboard over the rounded side piece and hot gluing it in place as she goes, shaping the curved top of a cardboard chest lid.

Once both rounded sides are glued in, you’ll probably have some extra length hanging off the end. Mark it with a ruler and trim it off with a utility knife or cordless electric cutter. I recommend the electric cutter; it’s much faster and easier on your hands.

Crystel lining up a metal ruler and marking with a pencil where to trim the extra cardboard length off the curved pirate treasure chest lid, while a young helper works at the table behind her.

Step 5: Attach the Lid With Packing Tape

To turn the lid into a working hinge, I used packing tape along the back seam where the lid meets the box on the outside, and I also opened the lid and taped the same seam on the inside to reinforce it. Taping both sides keeps the hinge strong.

Crystel pressing clear packing tape along the back seam where the curved cardboard lid meets the box, creating an outside hinge for a DIY treasure chest, with a cordless electric cutter on the table beside it.
Crystel holding the cardboard treasure chest lid open and smoothing packing tape along the inside of the hinge seam to reinforce it, as a young helper peeks over the box from behind.

Step 6: Cut and Glue Brown Craft Foam Planks

This is where your cardboard box starts turning into a wooden pirate chest. Use a metal square or a ruler to mark long strips on sheets of brown craft foam. These become the wood planks. Cut along your pencil lines with scissors.

Grab your hot glue gun and run a line of hot glue down the back of each foam strip and press it onto the DIY treasure chest. Leave a small gap between each plank so it reads like individual boards. The planks go all the way around the whole chest, lid and sides included.

Cutting brown craft foam along penciled lines with orange-handled scissors to make faux wood planks for a cardboard treasure chest, while a young helper holds a metal ruler on the table.
Crystel running a line of hot glue down a brown craft foam strip before pressing it onto the front of a cardboard treasure chest, where three foam planks are already lined up with small gaps between them to look like wood boards.

Tip: If you want the lid to open easily, leave a little gap in the foam along the back where the lid meets the box. You can see the gap I left in the first photo of Step 9.

Step 7: Add Black Foam Trim

To make the trim that looks like the metal bands on a real treasure chest, cut black craft foam into strips that are slightly thinner than your planks. Glue them along all the edges of the chest.

Crystel pressing a thinner strip of black craft foam along the bottom edge of the DIY treasure chest to mimic metal trim, with a matching black strip already framing the top edge and a young helper watching closely.
Crystel pressing black craft foam trim along the front edge of a DIY treasure chest now covered in brown foam planks on both the lid and base, with the rounded cardboard side still bare.

For the rounded sides of the lid, I used that same trusty mixing bowl to trace a curve onto black craft foam, then cut it into an arch.

Then I glued the arch around the rounded edge of each side, so it frames the curve of the DIY treasure chest lid.

Crystel cutting a curved arch out of black craft foam with orange-handled scissors, following lines traced from the same mixing bowl used for the lid sides, while young helpers trim their own foam scraps at the table.
Crystel fitting a rounded black craft foam arch over the planked side of the cardboard treasure chest lid to frame the curve like metal banding, as a young helper looks on from across the table.

Step 8: Make the Lock Detail

No treasure chest is complete without a lock! Draw a lock plate shape on black craft foam and cut it out. My helper took this job very seriously.

Glue the lock to the center front of the chest, just below the lid.

A young helper cutting a traced lock plate shape out of black craft foam with orange-handled scissors, next to the fully planked and trimmed DIY treasure chest.
Crystel pressing a black craft foam band into place along the front of the cardboard treasure chest, with the foam lock plate centered just below the lid, as a young helper watches from beside the table.

Step 9: Spray Paint With Red Primer

Once all the foam is on, take the chest outside and set it on a drop cloth (or a trash bag in my case). Here’s the back of mine before painting, where you can see the strip of cardboard I left uncovered along the hinge.

Spray the whole thing with primer. I used Rust-Oleum 2X Ultra Cover Flat Red, which dries to a ruddy, redwood brown. This one coat pulls the cardboard and two colors of foam together into one solid base. Any brownish color should do for this part.

Back view of the finished cardboard and craft foam DIY treasure chest sitting on a plastic drop cloth in the yard before painting, with a strip of bare cardboard left uncovered along the hinge so the lid can open freely.
Crystel spraying red primer over the entire cardboard treasure chest outdoors on a drop cloth, covering the foam planks and trim in one even reddish-brown coat, with fall pumpkins on the porch behind it.

If you want the inside of your chest to look nice, and not like moving boxes, go ahead and spray the inside as well.

Step 10: Paint the Trim Black

After the primer dries, bring the DIY treasure chest back inside and paint all the raised trim edges and the lock with black acrylic craft paint. You don’t have to be careful. It’s ok if some black gets on the wood plank part.

Crystel brushing black acrylic paint along the raised foam trim on the front of the curved lid, with the rounded side banding already painted and a paper bowl of black and brown paint on the table beside the cardboard treasure chest.
Crystel tipping the primed DIY treasure chest back and brushing black acrylic craft paint onto the raised foam trim along the bottom edge, with the front banding and lock already painted black and a young helper sitting nearby.

Step 11: Paint the Planks Brown

Next, brush brown acrylic craft paint over the wood plank sections. Don’t stress about perfect coverage. The streaky brushstrokes and bits of red primer peeking through are what make it look like real wood grain.

Crystel painting brown acrylic over the planks on the rounded side of the cardboard treasure chest lid, with the unpainted reddish primer still showing on the side of the base below for a clear before and after.
Crystel brushing dark brown acrylic paint over the front foam planks of the DIY treasure chest, leaving streaky brushstrokes that read like wood grain, with the black trim and lock already finished.

Step 12: Add Rub ‘n Buff to the Trim

This is where the magic happens. I rubbed Rub ‘n Buff in Antique Gold over all the black trim with a foam craft brush. The black underneath gives the gold so much depth, and suddenly that foam trim looks like old metal hardware.

Crystel holding a tube of Rub ‘n Buff and rubbing the metallic wax onto the black foam trim with her fingers, giving the front banding and lock of the DIY treasure chest a worn gold finish while the side trim is still plain black.

If you’ve been around here for a while, you know I have a serious love for Rub ‘n Buff. I used the same Antique Gold on my gold bathroom mirror and my DIY flocked ornaments. Every time, the black underneath is what makes the gold look like real metal instead of gold paint.

Front of the cardboard treasure chest after the Rub ‘n Buff step, with streaky aged gold metallic trim and a matching lock plate framing the dark brown painted foam planks.

Step 13: Fill Your Treasure Chest

Now for the fun part! I put an empty cardboard box in to fill space, tucked crumpled kraft paper into the chest, and piled plastic gold coins and colorful gems on top. A few strands of pearl necklaces draped over the front edge made it look like the treasure was spilling out.

Finished DIY treasure chest with an aged gold trimmed lid propped open, overflowing with gold coins, colorful gems, and pearl strands, while a skeleton reaches over the edge and fishing net hangs beside it.

How I Decorated the Trunk for Our Pirate Trunk or Treat

The treasure chest was the star, but the rest of the van setup was simple and budget friendly:

  • Brown kraft paper lined the whole cargo area and spilled down over the bumper onto the ground. Crumpling it gives it a rugged, rocky look.
  • Black tape held the paper up along the inside of the van.
  • A fishing net draped down one side for that shipwreck vibe.
  • A posable skeleton sprawled next to the chest with one bony hand reaching over the lid, like he’s still guarding his treasure.
  • Gems and gold coins to fill up the DIY treasure chest
Full pirate trunk or treat setup in an open van, with crumpled brown paper lining the cargo area, a draped fishing net, a skeleton sprawled beside the open cardboard treasure chest, and paper spilling down over the bumper onto the parking lot.

What I’d Add Next Time

I had big plans to glue faux vines around the edge and seashells onto the fishing net, but I ran short on time. If you have a little extra time, they’d be a fun finishing touch.

The Treasure Chest Saved the Day

We totally underestimated how many kids would show up and ran out of fruit snacks way earlier than planned. So we did what any good pirate would do and started handing out the jewels from the treasure chest. Honestly? The kids loved them more than the candy.

If you’re planning your own trunk or treat, a chest full of plastic gems is a great built-in backup treat.

📌 Pin This DIY Treasure Chest for Later

Save this to your Halloween or trunk or treat board so you’ve got it ready when it’s time to plan next year’s setup.

FAQ: Making a DIY Treasure Chest

What do you need to make a DIY treasure chest?

You need cardboard, brown and black craft foam, a hot glue gun, packing tape, and a utility knife or scissors. For the finish, you need red spray primer, black and brown acrylic craft paint, and Antique Gold Rub ‘n Buff.

How do you make a curved treasure chest lid out of cardboard?

Trace a large mixing bowl onto cardboard to cut two rounded side pieces that match the width of your box’s sides. Glue a flat sheet of cardboard, cut to the width of the chest, around the curves, then trim off any extra length.

How do you make a cardboard treasure chest look like wood?

Cover it in strips of brown craft foam with small gaps between them, so each strip reads as a plank. After priming, brush on brown acrylic paint and let the streaky brushstrokes act as wood grain.

How do you make the trim look like metal?

Glue black craft foam strips along the edges, paint them black after priming, then rub Antique Gold Rub ‘n Buff over the top. The black underneath makes the gold look like aged metal hardware.

What can you put inside a treasure chest for trunk or treat?

Plastic gold coins, colorful plastic gems, and pearl bead necklaces fill it out nicely. Bonus: they double as giveaways if you run out of candy.

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