This Baby Shark Costume DIY is sure to be a hit! I couldn’t let this Halloween pass us by without making a baby shark costume for my toddler! She loves this song and does all the hand motions to it.
With a new baby in the house, YouTube is our friend these days. This baby shark costume DIY is super easy, too! You can start with a hoodie and sweatpants, or make them from scratch using a pattern.
I included templates for the shark pieces – the teeth you add to the hood, the fin in the back and the tail! The front has iron-on vinyl with DOO DOO DOO DOO DOO DOO spelled out, just so no one misses the costume reference! (If you’re confused, type in ‘baby shark’ on YouTube) 
This was a really fun handmade costume to make, I used felt inside the tail and fin to make them sturdy and they stick out just right! Mae loved wearing this shark suit for these photos and I’m excited to see her dance to Baby Shark in it! DOO DOO CUTE!
I used a Navy polka dot French Terry from So Sew English for this, which will be perfect for a chilly Halloween night! I love this fabric, it’s super soft since it has rayon in it and has just the right drape for this costume! I also used plain white felt for the shark’s underbelly – really just to have a blank spot for words. I started with the Gemini Hoodie + Sweatpants pattern, which is one of my favorite things to make for babies! Last year I used it to make a bear hoodie and a cat costume! You can really make it into any animal and it’s also adorable in a cute floral fabric – you can see more pics here!
Materials FOr Baby Shark Halloween Costume
–the Gemini Hoodie + Sweatpants pattern
-1-2 yards blue or grey knit fabric
–1/2 yard white felt
–black iron-on vinyl and cutting machine
–Cricut EasyPress and Mat
–Doo Doo Design in Design Space
-printable shark templates (download below)
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the GEMINI baby track set pattern
Start from store-bought for Baby Shark Costume
If you want to start from a store-bought hoodie you’ll just need to print off the templates and sew them on. This is the easiest and quickest method and you can start from a jumpsuit, 2-piece sweat suit or even a dress! To do it this way, grab a yard of basic grey knit to match a grey sweatshirt material.
–Grey Knit Fabric
–Grey Footed Jumpsuit
–Grey Tracksuit
–Grey Girl’s Dress
Instructions to make a baby shark costume
Use 3/8″ seam allowance.
If you’re starting from the Gemini Hoodie + Sweatpants cut all the pieces as written, except the back bodice piece. Instead of cutting the back bodice on the fold, cut TWO pieces not on the fold, adding 3/8″ to center back for seam allowance.
Print off the shark costume templates from your home computer. Trim the edges and tape them together. The 3 pages fit together like so:
Cut 2 tail pieces from fabric (mirror image) and 2 fin pieces from fabric using the outer cutting lines. Use the inner cutting lines to cut 2 layers of felt.
Sew the tail pieces together, right sides together, leaving the top open. Trim the seam allowance and turn the tail right side out. Stuff the felt inside, holding them together as one piece. Topstitch around the tail about 1/4″ from the edge. Repeat with the fin pieces, leaving the straight edge open. Stuff and topstitch.
Sew the back bodice pieces together, sewing the fin in-between them, about 2-5″ below the neckline, depending on the size you are making.
When attaching the waistband to the bodice, stick the tail piece in between the layers.
Cut 1 oval from felt for the belly. I used the Cricut Maker with the rotary blade to cut mine so it was a perfect cut! I loaded the oval shape in the Cricut Design Space project right here. You can also cut this by hand. Cut the Doo Doo design out from iron-on and use the Easy Press to fuse it to the felt oval.
Sew the felt belly to the front of the hoodie.
Cut the felt teeth out on the fold. This piece may not be the right size, so measure to get it right. Sew the shark teeth to the inside of the hood.
Sew the pants as instructed with no modifications.
I think this costume will go perfectly with big sister’s mermaid costume!
