Tyler said he's leaving the hit show after two seasons to rededicate himself to Aerosmith, the band he fronts. The rock star said he loved every minute on the hit Fox singing contest but added, "it's time to bring rock back."
"After some long ... hard ... thoughts ... I've decided it's time for me to let go of my mistress 'American Idol' before she boils my rabbit," Tyler said in a statement, making a joking reference to the 1987 Michael Douglas-Glenn Close thriller "Fatal Attraction."
"I strayed from my first love, Aerosmith, and I'm back - but instead of begging on my hands and knees, I got two fists in the air and I'm kicking the door open with my band."
The band is currently on a nationwide tour with Tyler and has an album due out in the fall.
Tyler's "Idol" departure leaves original judge Randy Jackson and Jennifer Lopez, but the singer-actress' future with the show is cloudy.
In a phone interview with The Associated Press as the news about Tyler broke, Lopez said she was saddened to hear that he was leaving.
"I can't even imagine anyone else there right now because I've just spent two years sitting next to him," she said. "I love Steven, and we became close during that time. We were a great support for each other, on an adventure that neither one of us knew what it was going to be. So it's hard to hear that he won't be doing it."
Lopez also said Tyler's departure will play a role in her decision to stay or go. She has already expressed that there is a good likelihood that she will not be back.
"All hope is never lost, not all hope, but at the same time, there are too many things that I need to think about," she said. "I know they want me back, I know that I want to go back, but it's not as simple as that. When I started 'Idol' ... I signed on for one year. I didn't even think about doing it for two years, let alone three years. To make the decision to go back a second year was a big deal for me."
AP Television Writer Lynn Elber contributed to this report from Los Angeles.