Steve told The Sun: "After 12 years in Walford it is time for Phil Mitchell to take a break.
"I'm going to stick my mechanic's overalls in a locker while I take a look at other projects."
Phil Mitchell's character has been in EastEnders since 1990, when he arrived in Albert Square with his on-screen brother, Grant.
In real life, Steve, 43, is going out with Lucy Benjamin, who played his ex-girlfriend Lisa in the soap.
EastEnders was told off by TV watchdogs recently for a scene where Phil Mitchell beat up his nephew Jamie. Lots of viewers thought it was too realistic and disturbing.