The 37-year-old addressed a woman with the name Katy on the his show, "Brand X" and said people with the the same name are a pain for him, reports thesun.co.uk.
"Anyway, enough of you, I've had enough ar*e-ache from people called Katy in the last year," Brand said.
"Russell was in great form, having some banter with the audience. Then he came across this audience member who was named Katy. They were having some chat about whether Katy could satisfy her boyfriend in bed when, all of a sudden, Russell shouted the comment about ar*e-ache. It was a blatant reference to Katy Perry," a source from the show said.
Ever since the two announced their separation in 2011, Brand had never taken a dig at the 27-year-old singer, but could not stop himself from doing that now.
The divorce was finalised over this weekend.