Sheryl Lee Ralph (born December 30, 1955) is an American actress, singer, author, and activist. She made her screen debut in the 1977 comedy film A Piece of the Action, before landing her breakthrough role as Deena Jones in the Broadway musical Dreamgirls (1981), for which she received a Tony Award nomination for Best Actress in a Musical.

Ralph has appeared in a number of movies during her career. In 1991, she received the Independent Spirit Award for Best Supporting Female for her role in the drama film To Sleep with Anger. Her other film credits include The Mighty Quinn (1989), The Distinguished Gentleman (1992), Sister Act 2: Back in the Habit (1993), and Deterrence (1999). On television, Ralph starred from 1986 to 1989 in the syndicated sitcom It's a Living, and later had the leading roles in the short-lived ABC sitcom New Attitude (1990), and CBS medical drama Street Gear (1995). From 1996 to 2001, she starred as Dee Mitchell in the UPN sitcom Moesha, and from 2013 to 2015 as Maggie Turner in the Nick at Nite sitcom Instant Mom.

Sheryl Lee Ralph released her first book Redefining Diva: Life Lessons from the Original Dreamgirl (2012) by Simon & Schuster. In 2016 she played Madame Morrible in Wicked on Broadway.