Perry, 31, earned $135 million in the past 12 months, thanks to a huge worldwide "Prismatic" tour and endorsements deals with beauty companies like Coty and CoverGirl, Forbes estimated in a ranking released on Wednesday.
Swift, 25, was a distant second, with an estimated $80 million, despite some 8.6 million sales globally for her "1989" hit album and the start of a world tour.
Perry's latest album "Prism" has sold some four million worldwide since its release in 2013 and the "Roar" singer has been touring for most of the year.
British-American rock band Fleetwood Mac was placed third with $59.5 million although only two of its five current line-up are women. Nevertheless, the return of 1970s veterans Stevie Nicks and Christine McVeigh was seen as a key to the success of the band's year-long tour "On With the Show," Forbes said.
Lady Gaga was ranked fourth with $59 million—a long way behind her 2011 peak of $90 million when she was grabbing headlines with outrageous stunts and costumes.
Last year's top earner Beyonce slipped to 5th place with an estimated $54.5 million.
The Forbes list measures estimated pre-tax income from June 2014 to June 2015, and includes earnings from albums, touring, endorsements and other commercial deals. —Reuters
