Skip to Content

Mermaid Birthday Cake

Every little girl wants to be a mermnaid. This eay tutorial will teach you how to make a Mermaid Birthday Cake that is fit for a mermaid princess!

A beautiful Mermaid cake that any little girl would love for her birthday.

Decorating a Mermaid Birthday Cake

I think every little girl dreams of being a mermaid at least once in her life. This cake was made for a two sisters who were celebrating a joint summer birthday party. The theme was of course mermaid and it was held at the pool! I didn’t want to do much buttercream work for fear of melting in the summer heat. So fondant was the perfect choice.

Most people don’t care for the flavor of basic fondant, but this recipe was extra special and made with Jell-o so it tasted great and stayed soft. Simply Perfect!

Multiple shades of green and blue make up this Mermaid inspired cake.

 This mermaid cake was piece of cake!

Once the cake had a nice, clean crumb coat on and the fondant was made, it took me only 2 hours to decorate it. Trust me, this was faster and easier than a petal cake. My hand cramped something fierce when I made that cake.

Mermaid Scales decorated with glitter.

It does take some time to cut out all the little circles, and yes, that was a bit of a pain. However, the results were amazing . I loved it and more importantly, the birthday girls loved it.

A Mermaid inspired cake for a special birthday party.

I used the green and blue fondant that was colored with the jello, but I also supplemented the dark green and light turquoise/ sea-foam color from some premade fondant.   I really liked the added color intermixed.

The brighter blue and green color was achieved by added pearl dust to the circles. In all, there are six different shades of green and blue on this cake.

Then, just to add a little extra sparkle, I added some gold disco dustover top. Just because every birthday cake should shimmer!

1 dd Mermaid Cake (14)

This recipe is part three of a three part series including Jello Fondant and How to Crumb Coat a cake.


Yield: 1 cake

Mermaid Birthday Cake

Mermaid Birthday Cake

This Mermaid inspired cake made the best birthday cake for a 9 year old and 12 year old celebration!

Prep Time 3 hours
Cook Time 3 hours
Total Time 6 hours



  1. Have you cake covered in your frosting and in the fridge.
  2. Prepare your plastic mat with a thin layer of shortening to prevent the fondant from sticking.
  3. Break off a chunk of the jello fondant (a little larger than a golf ball) and warm it up in your hands. Roll smooth using the guides on the roller to get it even. Use the piping tip to cut out circles.
  4. Set half aside and add a thin layer of luster dust over them with a dry paint brush.
  5. Continue to make circle cut outs with all the colors you intend to use. I used about 75% more jello fondant than premade fondant.
  6. Start at the bottom of the cake and randomly add circles to the base. The should stick to the buttercream frosting without need for any other adherent.
  7. Offset the second row and continue around the cake. I had 5 rows going around my cake, the last one, bending over from the top down the side.
  8. For the top, start at the outer perimeter and go around in an overlapping fashion. Continue to build toward the center, then overlap the final circles in the center as best as possible.
  9. Cover and refrigerate until ready to sing Happy Birthday.

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 3

All Things Mermaid - Ms. Alisha Carlson

Friday 6th of November 2020

[…] Mermaid Cake | Pint Sized Baker […]

50+ Charming Birthday Cakes for Grown Ups – With Recipes! ⋆

Wednesday 23rd of October 2019

[…] Mermaid Cake […]


Friday 4th of August 2017

I made the fondant but it's hard to cut and not easy to eat...

Karyn Granrud

Thursday 10th of August 2017

It most likely got dry. Did you coat it in shortening and wrap it well to store it? Did you put it in the fridge once you decorated the cake? The fridge will dry it out and make a mess of it. Most people pull off the fondant and don't actually eat it, but the marshmallow version usually stays soft and yummy to eat. Not sure what happened.

20+ The Best Mermaid Theme Party Ideas - Natural Beach Living

Thursday 8th of June 2017

[…] gorgeous Mermaid Cake for someone that loves to make inspiring Birthday […]


Monday 27th of April 2015

This cake is absolutely GORGEOUS!!

Karyn Granrud

Sunday 10th of May 2015

Thanks so much. It's so easy to make as well.

Skip to Recipe