Katy Perry Rocks Black Bikini For Ice Bucket Challenge - Watch Now!

Check out Katy Perry showing off her body in a bikini while completing the ALS Ice Bucket Challenge!

“Thank you @thestevetisch @aw & @hellogiggles for nominating me for the ALS #theicebucketchallenge I now nominate @madonna (ALSO SORRY THIS IS SO LOUD & ANNOYING) �’�,” the 29-year-old singer shared with the video on Instagram after she was nominated by close pal Allison Williams. Check out Allison‘s video after the cut!

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Katy isn’t the only one doing the challenge in a bikini, Nina Dobrev, Iggy Azalea, and Emmy Rossum all wore bikinis as well!

Click inside for Allison Williams’ Ice Bucket Challenge video…