The pop superstar will take to the stage at The O2 in London on February 22 to perform her new single 'Chained to the Rhythm' and will join previously announced performers Ed Sheeran, Bruno Mars, Skepta, Little Mix, The 1975, Robbie Williams and Emeli Sande.
Katy, 32, announced the news in a statement which read: "I'm excited to come back to one of my favourite countries, where most of my favourite musical influences come from.
"After three years, I'm excited to return to the BRITs' stage to kick off a new era of purposeful pop."
And the blonde beauty - who previously bagged herself a BRIT in 2009 for Best International Female Solo Artist - also teased fans with the news on Twitter as she claimed she was excited to bring the "second chapter" to her new song to the prestigious event, following her debut performance of the track at the Grammys in Los Angeles on Sunday (12.02.17).
She tweeted: "YAY 2nd chapter of #ChainedToTheRhythm continues in LONDON! (sic)"
Katy - who is a relationship with Orlando Bloom - had been previously reported to be talks to sing at the ceremony as this year's "blockbuster act".
And Katy, like all of this year's performers, has been given her own special BRITs emoji.
A post on the official BRIT Awards Twitter account (@BRITs) unveiled the creation along with the message: "Of course #BRITs performer @katyperry has an official emoji and OF COURSE it's adorable!!! #KatyPerryBRITs #BRITs (sic)"
The BRIT Awards with Mastercard will be hosted by Emma Willis and Dermot O'Leary and will be broadcast live on ITV.