Born Mary Kathleen Turner in Springfield, Missouri, Turner's parents were career diplomats, and she lived in four foreign countries--Canada, Cuba, Venezuela, and England while growing up. Turner has two brothers and a sister. She was a gymnast as a teenager. While attending high school in London, she also took classes at the Central School of Speech and Drama. Her father, Richard Turner, grew up in China and was a foreign services diplomat who was imprisoned by the Japanese for four years during World War II. When her father died of cancer in 1973, the family moved back to Springfield. Turner's brother Stephan was married to designer Donna Karan.

She attended Southwest Missouri State University at Springfield for two years, then gained her Bachelor of Fine Arts degree from the University of Maryland Baltimore County in 1977. In 1978 the 5'10", husky voiced Turner was hired as the second Nola Turner on NBC daytime soap The Doctors, but was fired the next year because the producers felt she was "not hot enough". Turner had the last laugh as she became a movie star a few years later in Body Heat, which many consider one of the sexiest films (with Turner giving one of the sexiest performances) in the history of cinema. Turner remained a film star up to the early 1990s, but has since rarely appeared in major productions.