This easy-to-make Bowser Jr. costume is a fun, original choice for any Super Mario fan who wants a unique look for school parades or Halloween. It echoes Bowser’s style but adds playful details like his signature giant paintbrush and a pint-sized clown car trick-or-treat bucket. The outfit is built around a comfy sweatsuit, so it’s warm and practical for chilly fall weather.
The following tutorial walks through creating the hoodie details, the shell, the oversized paintbrush prop, and the clown car bucket. Most materials are inexpensive and easy to work with, and the result is a standout costume your child will love wearing.
Supplies Needed
To assemble the Bowser Jr. costume, gather:
- Yellow zip-up hoodie
- Yellow sweatpants
- Green fleece (about 1/2 yard for a child; more for an adult)
- White fleece (about 1/2 yard)
- Pale yellow fleece or substitute white (about 1/4 yard)
- White felt
- Red felt
- Polyfill stuffing
- White square napkin or bandana
- Velcro
- Black, red and purple fabric markers
- Red feathers
- 2″ wide black elastic (for straps and cuffs)
- Sewing machine (or hand-sewing supplies)
For the giant paintbrush prop:
- Cardboard wrapping paper tube
- White pipe cleaners
- Clear domed cup lid
- Two 3″ wood circles or equivalent
- Silver, yellow, blue and white duct tape or matching paint
- Orange vinyl or orange paint
- Blue paint
- Fabric scissors and a hot glue gun
For the Clown Car trick-or-treat bucket:
- Black cauldron-style trick-or-treat bucket
- White duct tape
- Green, black, red and orange felt or faux leather
Step-by-Step Bowser Jr. Costume Tutorial
Follow these steps to create the main costume pieces.
- Cut an oval from yellow fleece slightly shorter than the front of the hoodie (from about 2″ below the zipper top to the top of the bottom band).
- Trim the oval in half vertically, creating two matching pieces.
- Attach one half to each side of the hoodie along the zipper. Stitch in place and sew horizontal lines 1–2″ apart to mimic Bowser Jr.’s belly segments.
- Make two small white felt cones (about 3″ tall). Sew or hot-glue each into a cone, stuff with polyfill, and attach one to each side of the hood to form spikes.
- Create Bowser Jr.’s red hair by wrapping red feathers in a 2″ x 12″ strip of black felt and attaching it to the top of the hood with hot glue.
- Sew or glue black elastic to each sleeve cuff for the spiked-bracelet look.
- Fold a white napkin or bandana diagonally to form the face bandana.
- Draw and color Bowser Jr.’s mouth on the bandana using fabric markers.
- Attach Velcro to the two narrow corners of the bandana and to the sides of the hood so the bandana fastens comfortably. If the bandana is large enough, you can also tie it.
- Cut two green fleece ovals sized to the child’s back (roughly shoulder blade to top of hips and a bit wider than the back).
- Cut a white felt oval about 2″ smaller than the green pieces and set aside.
- On one green oval, draw hexagon patterns with a fabric marker. Use this as a guide to stitch the hexagon lines to give texture to the shell.
- Place the two green ovals right sides together, then layer the white felt oval on top (white facing the clean side of green). Pin and stitch around the edges, leaving a 4″ gap for turning.
- Turn the shell right side out, stuff with polyfill, and close the opening by hand-stitching or hot-gluing.
- Make a rim: cut a fleece strip about 7″ wide and a couple inches longer than the shell circumference, fold it lengthwise, sew the long edge, turn and stuff. Hot-glue this strip around the shell edge, overlapping the ends and securing them.
- Create ten white felt cones (about 3″ tall), stuff them, add a 1/2″ red felt band to each base, and hot-glue one cone onto each hexagon on the shell.
- Add black elastic straps: attach two straps to the shell so it can be worn like a backpack, stitching or gluing the elastic securely and covering raw attachment points with extra white felt if desired.
- Complete the look with yellow pants and shoes.
Giant Bowser Jr. Paintbrush Tutorial
Bowser Jr.’s Magic Brush is an iconic accessory and makes a dramatic prop. Build a lightweight, oversized brush using cardboard, tape, pipe cleaners and a few simple details.
- Shorten the cardboard tube by cutting partway up and overlapping the ends so the tube narrows toward the bottom. Glue to secure.
- Wrap the tube in yellow duct tape for the handle color.
- Cover two round discs in white on the faces and blue on the sides (tape or paint) and attach one disc to each side of the top area.
- Add an orange silhouette detail (Bowser shape or simple emblem) with vinyl or paint.
- Wrap the tube’s top in silver tape, covering the open edge, and adhere a clear domed cup lid to the top, then cover that in silver as well.
- Bunch many white pipe cleaners together, glue their tips to create a brush head, paint the tips blue, and attach the base of the pipe cleaner bundle to the domed lid with hot glue.
- Finish with two small silver spikes on either side of the brush head for an extra Bowser-like touch.
Clown Car Trick-or-Treat Bucket Tutorial
A miniature clown car bucket is a quick, playful prop that completes Bowser Jr.’s look without building a full vehicle. Transform a basic bucket into a cartoon car with felt accents and white tape.
- Cover the bucket and handle with white duct tape to create a clean base.
- Cut two eyes from black felt, red accent pieces, an orange mouth, and green propeller shapes and a center circle.
- Draw details on the mouth with a fabric marker and hot-glue all felt pieces onto the taped bucket in the arrangement shown.
- Glue a strip of green felt around the bucket rim to finish the look.
Costumes to Pair with Bowser Jr.
If you want a duo or group theme, consider pairing Bowser Jr. with:
- Bowser & Bowser Jr. — a classic parent-and-child combo.
- The Koopalings — a colorful group option that fits the Koopa family vibe.
- Classic Mario characters — Mario, Luigi, Yoshi or Princess Peach make a fun broader group.
This Bowser Jr. costume is a great mix of comfortable clothing and eye-catching details. The hoodie and pants can be repurposed throughout the season, and the shell, paintbrush and clown car add playful, recognizable touches. Happy trick-or-treating and have fun creating the costume!