The 24-year-old singer was spotted with the Good Charlotte star at the nightclub Lavo after she performed a Valentine's Day gig at Hard Rock Hotel's Wasted Space.
A witness told People that there was "some chemistry" between the pair. Meanwhile, Madden apparently "danced for Perry" during his DJ set.
Madden, 29, split from Hilton in November after nine months. The couple claimed that they were "too different" and had "grown apart".