Eileen Brennan (September 3, 1932 – July 28, 2013) was an American actress who was known for her versatile performances in film, television, and theater. She was nominated for an Academy Award for Best Supporting Actress for her role as Captain Doreen Lewis in the 1980 comedy film Private Benjamin. She also won a Primetime Emmy Award for Outstanding Supporting Actress in a Comedy Series for her role as Mrs. Hughes in the television series Newhart.

Brennan was born in Los Angeles, California, and began her acting career in the theater. She made her Broadway debut in 1963 in the musical Little Mary Sunshine. She went on to appear in several other Broadway musicals, including Hello, Dolly! and Annie.