June Lockhart, renowned actress known for her maternal roles in the TV series Lassie and Lost in Space, passed away at 100 from natural causes in Santa Monica, California, on October 23, 2025. Her death was confirmed by her family to Variety magazine. The Emmy-nominated and Tony-winning actress left a legacy spanning over seven decades in film, theater, and television.
Born in New York in 1925 to actors Gene and Kathleen Lockhart, she began performing early and became a household name through her iconic roles. Her contributions shaped family-oriented and sci-fi television, earning her two stars on the Hollywood Walk of Fame.
Early career in theater and film
June Lockhart debuted on stage at eight in Peter Ibbetson in 1933, influenced by her actor parents. By 13, she appeared in A Christmas Carol, kickstarting her film career alongside her family.
At 19, she signed with MGM, starring in films like Meet Me in St. Louis and Sergeant York, often in supporting roles. Her Broadway breakthrough came in 1947, winning a Tony Award for best newcomer in For Love or Money, a milestone in her early career.
Breakthrough with Lassie
Lockhart’s role as Ruth Martin in Lassie from 1958 to 1964 on CBS cemented her as a TV icon. Playing the adoptive mother of Timmy, she brought warmth to the series about a heroic collie.
Her performance earned an Emmy nomination for best actress in a drama. The show, running from 1954 to 1974, drew millions of viewers weekly.
Ruth Martin guided Timmy through moral lessons tied to Lassie’s adventures.
Lockhart replaced Cloris Leachman, maintaining the show’s family appeal.
Her bond with co-star Jon Provost extended off-screen for decades.
Sci-fi legacy in Lost in Space
In Lost in Space (1965-1968), Lockhart played Maureen Robinson, a scientist and mother navigating a stranded family in space. The CBS series became a sci-fi classic, blending adventure and family dynamics.
The role earned her a second Emmy nomination. Her chemistry with co-stars like Bill Mumy and the show’s robot defined its enduring popularity.
June Lockhart, a popular actress of the 1950s and ’60s known for her roles in “Lost In Space,” “Lassie” and “Meet Me in St. Louis,” died of natural causes on Oct. 23 in Santa Monica, Calif. She was 100. https://t.co/gwkQkszWjh pic.twitter.com/MXqAUvG17Y— Variety (@Variety) October 25, 2025
Later roles and contributions
Lockhart remained active, appearing in Petticoat Junction, General Hospital, and voicing a role in The Ren & Stimpy Show in 1993. In 2021, she voiced a cameo in Netflix’s Lost in Space reboot, honoring her original role.
She also engaged in public events, including a 2012 NASA appearance discussing the Curiosity rover, tying her sci-fi work to real space exploration.
Personal life and advocacy
Lockhart lived in Santa Monica until her passing at 9:20 p.m. on October 23, surrounded by her daughter and granddaughter. Her family requested donations to The Actors Fund and International Hearing Dog instead of a public memorial.
Her advocacy for animal rights, inspired by Lassie, and support for hearing assistance dogs reflected her off-screen values.
Enduring influence on audiences
Lockhart’s roles in Lassie and Lost in Space shaped TV’s portrayal of family and adventure. Fans credit her with inspiring interest in science and pet care. She amassed over 100 credits across film and TV, including Beverly Hills 90210.
