Nancy Kelly (March 25, 1921 – January 2, 1995) was an American actress, born in Lowell, Massachusetts. Nancy was a child star, who had made so many movies by the time she was nine years old, that Film Daily called her "the most photographed child in America due to commercial posing."

She did not have a particularly successful adult career, although she did win a Tony Award for her performance in The Bad Seed, which she followed up by starring in the film version and receiving a nomination for the Academy Award for Best Actress.

She was the sister of actor Jack Kelly.