Karen Trust Grassle (born February 25, 1942) is an American actress, known for her role as Caroline Ingalls, the wife of Michael Landon's character and the mother of Melissa Gilbert's character, in the NBC television drama series Little House on the Prairie.
Grassle graduated from Ventura High School in 1959, and afterward enrolled in Sophie Newcomb College (Tulane University, 1959–60) and then the University of California, Berkeley. She graduated with two BA degrees in 1965, one in English, the other in Dramatic Art. She received a scholarship to the Royal Academy of Dramatic Art in London.
Grassle's first acting job in New York City was in the short-lived 1968 play The Gingham Dog. Grassle played in Butterflies are Free at the Elitch Theatre in Denver, Colorado, in June 1972, along with Maureen O'Sullivan and Brandon deWilde, who was killed before leaving town after the performances ended.