The retro image shows the singer swinging through a jungle wearing a busty animal print bra and leafy skirt.
An official video is confirmed for 5 September, while the single will be released Sunday 1 September (a week earlier than originally thought).
Katy's new album Prism is then expected to drop on 22 October. Busy!
She will also close this year's iTunes Festival, which chart-rival Lady Gaga kicks off in London this weekend.
So, are you liking Katy's fierce jungle poster?
Watch the lyric video for Katy Perry, Roar below...
KATY PERRY TEASES WILD 'ROAR' VIDEO
ALL THE WINNERS FROM THE MTV VIDEO MUSIC AWARDS
READ ALL OUR MUSIC NEWS