The 'I Kissed A Girl' singer, who is currently touring around Australia, beat Jennifer Hawkins and Miranda Kerr to top the Aussie version of FHM's annual list.
Perry told Perth Now: "That's amazing. I won? Really? Wow I can't believe it. I don't know what the criteria is for this award, but I endorse it wholeheartedly."
Others celebrities who made the list included Ruby Rose, Delta Goodrem, Rachael Finch, Megan Gale, Jesinta Campbell and Erin McNaught.
The Royal Family's latest addition - the Duchess of Cambridge, Kate Middleton - came in at 98. Today presenter Lisa Wilkinson was given the number 99 spot, while Helen Mirren made her debut in 96th place.
Mirren said: "It's flattering of course and I will accept that. But I hate the pressure that women put on other women constantly. I don't like the pressure men put on women even worse, but it really makes me angry when women put pressure on other women. You know, stop! Stop it!"
Perry recently came second in the 'Sexiest Woman In The World' list for the UK version of the men's magazine. Rosie Huntington-Whiteley was awarded first place.
