DIY Ghost Mermaid Costume

heather handmade sewing

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Learn how to make a DIY ghost mermaid costume with a mermaid dress and a white cape. This costume is the perfect mix of cute and creepy.

My kids love wearing cute or pretty costumes, but they also love being creepy and scary. My daughter wanted that this year, but we had to throw around some ideas. We’ve already done a lot of the scary Halloween characters in years past, and we’ve even done a skeleton mermaid.

We finally decided on a ghost mermaid because it’s cute and creepy. I’ve made both lots of ghost things and mermaid things, so I knew I could combine them. I tried looking up ghost mermaid costumes, but I only found pictures of ghost mermaids so we kind of invented a new character!

diy ghost mermaid costume

The parts of this costume are the mermaid tail dress, the white ethereal cape, and the mermaid hair. These are what I chose for the costume, but you can switch up the pieces to make it yours.

diy ghost mermaid costume

I already had the wig, so I just made the dress and the cape. They are very simple sewing projects so it would be easy to recreate it!

My favorite way to make a ghost scary is to add the netting cape to make the costume seem transparent. The way the bottom of the cape is shredded and spread out just makes the costume for me.

diy ghost mermaid costume

Do you love making costumes? Try one of these:

diy ghost mermaid costume

DIY Ghost Mermaid Costume


diy ghost mermaid costume supplies

Fold the scale fabric so that the scales are facing away from each other. Lay the t-shirt on top. Line up the armpit with the top of the fabric.

Cut a rectangle 3/8 inch wider than the t-shirt. The length should be from the armpit to about 10 inches below the hem of the t-shirt.

cut two rectangles of scale fabric

Match up the two rectangles with right sides together. Pin along each side.

pin rectangles right side together

Sew the two sides with a 3/8 inch seam allowance with either a zigzag stitch or a serger. Learn how to sew knit fabric and how to sew knit fabric with a sewing machine.

sew the rectangles into a tube

Cut a circle skirt for the fin of the mermaid tail. The inner circle should be the circumference of the bottom of the tube, and then the length should be from the bottom of the tube to the floor. (There’s a free calculator in this free circle skirt pattern.)

cut scale fabric circle skirt

Divide the bottom of the tube into four equal sections. Divide the top of the fin circle skirt into four equal sections.

divide the tube and skirt into four sections

Match up each section with right sides together and pin. Pin in between each pin so you have at least 8 pins.

pin the skirt to the tube

Sew the skirt pieces together at 3/8 inch seam allowance with a zigzag stitch or a serger.

sew the skirt to the tube right sides together

Slip the tube onto the t-shirt and line up the top with the armpits. Pin the skirt to the t-shirt.

pin the tube to the white t-shirt

Sew the skirt to the dress with a zigzag stitch.

sew the tail to the t-shirt

Cut a sheer white curtain to shoulder to floor length. Cut slits along the bottom to make a shredded look.

cut curtain and shred the bottom

Cut a piece of elastic that can sit on the shoulders comfortably. Use a safety pin to thread it through the casing of the curtain.

thread the elastic through the casing

On one side hand sew a button through the edge of the casing and through the elastic to hold it in place.

On the other side tie a loop in the elastic and secure it to the edge of the casing with some simple hand stitches.

tack the loop and button at the end of the casing

Put all the pieces together for the costume. If you don’t want to use a wig you can add a hood to the top of the curtain instead.

diy ghost mermaid costume

If you make something using this sewing project, I’d love to see! Please share it on social media with the hashtag #heatherhandmade and tag me!

diy ghost mermaid costume
heather sewing

I believe small sewing moments can create great joy. Find your own “right” way to sew. -Heather

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