Jeanne Marie Tripplehorn (born June 10, 1963) is an American actress. She began her career in theater, appearing in several plays in the early 1990s, including Anton Chekhov's Three Sisters on Broadway. Her film career began with the role of a police psychologist in the erotic thriller Basic Instinct (1992). Her other film roles include The Firm (1993), Waterworld (1995), and Sliding Doors (1998).

On television, she starred as Barbara Henrickson in the HBO drama series Big Love (2006–11) and as Dr. Alex Blake in the CBS police drama Criminal Minds (2012–14), and also received an Emmy nomination for her role as Jacqueline Kennedy Onassis in the HBO television film Grey Gardens (2009).