The TV project is expected to air in September 2011, which would coincide with the end of Winfrey's weekday talk show.
Thompson has produced TV biopics about Lucille Ball and Desi Arnaz, and Sonny and Cher.
He says he's a huge Oprah fan and that he's still shopping for a network that would air the film. An unknown will likely be cast to play Winfrey.
A spokesman for Winfrey's Chicago-based Harpo Productions declined to comment.
The Associated Press contributed to this report.