Joanne Gignilliat Trimmier Woodward was born on February 27, 1930, in Thomasville, Georgia, the daughter of Elinor (née Trimmier) and Wade Woodward Sr. Her middle names, "Gignilliat Trimmier", are of Huguenot origin. She was influenced to become an actress by her mother's love of film. Her mother named her after Joan Crawford. She has an older brother, Wade, Jr.
Attending the premiere of Gone with the Wind in Atlanta, nine-year-old Woodward rushed into the parade of stars and sat on the lap of Laurence Olivier, star Vivien Leigh's partner. She eventually worked with Olivier in 1977 in a television production of Come Back, Little Sheba. During rehearsals, she mentioned this incident to him, and he told her he remembered.
Woodward lived in Thomasville, then lived in Blakely and Thomaston before her family relocated to Marietta, Georgia, where she attended Marietta High School. She remains a supporter of Marietta High School and of the city's Strand Theater.
The family moved once again to Greenville, South Carolina, when she was a junior in high school, after her parents divorced. She attended and graduated from Greenville High School. She also performed at Greenville's Little Theater.
Woodward majored in drama at Louisiana State University, where she was an initiate of Chi Omega sorority, then headed to New York City to perform on the stage. There, she studied at the Actors Studio and also studied under Sanford Meisner in the Neighborhood Playhouse School of the Theatre.