The 70-year-old is getting ready for the release next month of a memoir about his life with Farrah Fawcett, who died of cancer in 2009.
"Although I was shocked and stunned by the news, I feel fortunate that it was detected early, and according to my extraordinary team of doctors, the prognosis is positive for a full recovery," O'Neal said in a statement. "I urge everyone to get regular check-ups, as early detection is the best defense against this horrible disease that has afflicted so many."
CORRECTION: In an earlier press release, Ryan O'Neal's spokesman said the actor had stage 4 prostate cancer, but the spokesman now says he has stage 2 prostate cancer.
