Family
- great-grandfather George Dern: Served as Secretary of War under Franklin Roosevelt; opposed the development and use of the atomic bomb; also served as governor of Utah
- father Bruce Dern: Married to Diane Ladd from 1960-1969; best-known as the caretaker in "Silent Running" (1972) and as Capt. Bob Hyde in "Coming Home" (1978); also played a recurring role on the HBO series "Big Love"
- mother Diane Ladd: Married to Bruce Dern from 1960-1969; best known for her Oscar nominated role as Flo in the film "Alice Doesn't Live Here Anymore" (1974); appeared with daughter in the films "Wild at Heart" (1990) and "Rambling Rose" (1991)
- step-mother Andrea Beckett: Married Bruce Dern in 1969
- step-father Robert Hunter: Married Diane Ladd in February 1999
- great-uncle Archibald MacLeish:
- great-cousin Tennessee Williams: Second cousin of Diane Ladd
- godmother Shelley Winters:
- sister Diane E Dern: Born in November 1960; drowned at age 18 months on May 18, 1962, five years before Laura was born
- son Ellery Walker Harper: Born Aug. 21, 2001; father, Ben Harper
- grandmother Mary Lanier: Mother of Diane Ladd
- daughter Jaya Harper: Born Nov. 28, 2004; father, Ben Harper
Companions
- Ben Harper: born c. 1969; dating as of late 2000; he was previously married and divorced
- Billy Bob Thornton: dating as of March 1997; met on famous "coming out" episode of "Ellen" (ABC); in 1999 announced plans to marry; separated in 2000 after Thorton unexpectedly married actress Angelina Jolie
- Jeff Goldblum: formerly married to Geena Davis; starred together in "Jurassic Park" (1993); engaged to be married on December 25, 1994; separated by 1996
- Kyle MacLachlan: together c. 1985-89
- Renny Harlin: later married Geena Davis
- Treat Williams: dated c. 1984
