16 Best Alien Costume Ideas for 2021 (DIY + More)





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Last Updated: September 24, 2021

The holidays are a lovely time of year where we all get to get together with loved ones and friends, eat great food, and get creative! But when I say that, I don’t mean Christmas – I’m talking about the most creative holiday of all: Halloween. 

Honestly, it’s never too early to start thinking about your Halloween costume, because there are thousands of options! Everything from sexy to funny, weird, or even spooky. And for that reason, we’re going to focus on all of the above when it comes to alien costume ideas. 

We’ve picked out costumes for everyone, including adults, teenagers, and even children. If you’re ready to get a little bit weird and X-files-y, keep reading to find some of the most unique alien costume designs!


Best Store-Bought Alien Costumes

Alien Babe


To start, this sexy, reflective costume is perfect for a woman trying to appear as if she was from another galaxy.

Just add the short green wig & alien gun, or even top it off with a matching alien mask. This costume has the total Guardians of the Galaxy vibe going on & we’re living for it!


Alien Cheerleader

If you want something a little more unique than just an alien, try out this alien cheerleader costume from Dolls Kill. It comes with everything you need (even matching panties).

Just grab some black or silver combat boots to finish the outfit off and you’re ready to go!


Adult Alien Pick Me Up


This is a more goofy-style alien costume, perfect for both men and women! This silly costume demonstrates a giant green alien holding the wearer up like a baby. This type of costume would definitely bring smiles to everyone’s face & make heads turn. Not to mention, it would be a great costume to enter into a costume contest!


Full Body Greenman Suit


If you’re ready to commit to a full-body suit, this Greenman alien suit is perfect for you. With a Spider-Man sort of style, this suit will have you walking around like the next addition to the Avengers. It’s easy to put on, mysterious, & also made of spandex, so you know it’s comfy! Trust us, people are going to have to look twice when they see you!


Ruby’s Alien Boys Child Space Creature Costume


Now, if you have a kid to dress up, this space creature costume is an excellent choice for helping your child live their dream in an aliens outfit. The coolest part about this costume is it isn’t just a regular green alien, it also comes with a mystical-looking hooded robe to make your child feel like the ultimate alien king! Talk about fun & exciting! Your child will love showing off a costume like this to all his friends any day!


Alien Catsuit Bodysuit


Now, if you’re a lady looking to dress like an alien in a skin-tight suit to show off your rocking bod, this catsuit is for you. Stretchy & decorated with glitter for that space creature feel, this has the total alien princess vibe going on & we’re loving it! With antennas & some sexy heels, this costume will have you looking like an alien model effortlessly. It also has the ability to be zipped down to reveal the goods, if you’re about that life (hey, we don’t judge!). 


Smiffys Fever Women’s Space Cadet Costume


Next, nothing says Zenon quite like this outfit! With the total galactic beauty vibe going on, this is the perfect alien costume if you’re going for sexy. On top of the hot outfit & pink hair, a great addition would be antenna! You could even add a weird sci-fi crown to give off a galactic princess vibe. So get the girls together, & let’s go stop some alien scum! 


Alien Halloween Onesie Costume


On a more cutesy side is this Disney Halloween onesie. Taking a step back to the good ole days of Toy Story, this cute alien costume makes use of comfort, childhood nostalgia, & the cuter side of Halloween. So, if you aren’t a fan of goofy costumes, skin-tight outfits, or something scary, this adorable onesie will be perfect for you. Please hold while I order mine immediately!


Child’s E.T. Costume (Toddler)


This adorable blast from the past is an excellent outfit for toddlers! This cute E.T. costume is perfect to transition kids into alien themes without scaring them too much. It’s comfy, easy, & will have all your fellow parent friends jealous of your great idea! Not to mention, it’s kid-friendly & will have your child growing up watching all the right movies! It definitely gets my vote! 


DIY Alien Costume Ideas

Back to the Basics


Although this isn’t entirely DIY, you can create your own sexy alien costume pretty easily for cheaper than buying an already put together costume. All you need is:

Make sure to add some extra touches with makeup!


No-Sew DIY Alien Baby Costume


Taking it back to more kid-friendly is this adorable & easy to make a baby costume that requires no sewing. This cute costume displays a simple outfit with a long sleeve green shirt, green pants, & then a headband with two-point ears, antennas & 3 alien eyeballs. It’s easy & probably the most adorable alien costume I’ve ever seen! Don’t miss out on this cutie pie!


Family Alien/Astronaut Set


And lastly, another great family astronaut/martian costume idea is this beauty. It’s a fun way to let your kids dress up like astronauts & let their imaginations run wild. Honestly, it doesn’t look like it requires much, mainly just piecing things together & maybe a little makeup! Overall, it’s a simple costume idea that the whole family will love! 


Easy “Earth Sucks” Retro Alien


With a more 80s style look, this easy alien costume is perfect for the lazy treat or treater or someone running out of time to find a costume. Basically, you just create a shirt that says, “earth sucks,” style your hair in an old-fashioned way, throw on some crazy colors & clothing pieces, & you’re done! See, who said that DIY costumes had to be fancy? 



Family Steampunk Alien Set


Now, if you’re looking for a P.G. homemade alien costume idea for the whole family, there’s always this incredibly creative steampunk alien idea. This idea incorporates family-friend ideas for everyone in your family, including top hats, bizarre colored dress draped in lights, steampunk goggles, & wild face paint designs that would be fun for everyone!

Bottom Line

In conclusion, no matter what alien Halloween costume idea you choose, I hope you were able to find some inspirational ideas that get your mind racing! Remember, have fun, & get creative! Your costume doesn’t have to be traditional or even spooky – & let’s be honest, it’s a lot more fun when it’s not! Let that wild side go crazy & create the weirdest-looking alien imaginable!

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