[5] His mother, Jewell Mae (née Risley; 1918–2005), was an art teacher at Bell Gardens High School, and his father, Paul Eual Lasseter (1924–2011), was a parts manager at a Chevrolet dealership.

[14][15][16] Lasseter is a fraternal twin; his sister Johanna Lasseter-Curtis, who became a baker based in the Lake Tahoe area, is six minutes older.

Lasseter was taught by three members of Disney's Nine Old Men team of veteran animators—Eric Larson, Frank Thomas and Ollie Johnston—and his classmates included future animators and directors like Brad Bird, John Musker, Henry Selick, Tim Burton, and Chris Buck.

[25] While at CalArts, Lasseter first started working for the Walt Disney Company at Disneyland in Anaheim during summer breaks and got a job as a Jungle Cruise skipper, where he learned the basics of comedy and comic timing to entertain captive audiences on the ride.

[17][26] Upon graduating in 1979, Lasseter immediately obtained a job as an animator at Walt Disney Productions mostly due to his success with his student project, Lady and the Lamp.

[27] In the fall of 1979, Disney animator Mel Shaw told the Los Angeles Times that "John's got an instinctive feel for character and movement and shows every indication of blossoming here at our studios ...

[28] However, after 101 Dalmatians (1961), which in Lasseter's opinion was the film where Disney had reached its highest plateau, he felt that the studio had lost momentum and was often repeating itself.

[29][30] Between 1980 and 1981, he coincidentally came across some video tapes from one of the then new computer-graphics conferences, who showed some of the very beginnings of computer animation, primarily floating spheres and such, which he experienced as a revelation.

[17] But it was not until shortly after, when he was invited by his friends Jerry Rees and Bill Kroyer, while working on Mickey's Christmas Carol (1983), to come and see the first light cycle sequences for an upcoming film entitled Tron (1982), featuring state-of-the-art computer-generated imagery (CGI), that he saw the huge potential of this new technology in animation.

Lasseter realized that computers could be used to make films with three-dimensional backgrounds where traditionally animated characters could interact to add a new level of visually stunning depth that had not been possible before.

[31] Lasseter and his colleagues unknowingly stepped on some of their direct superiors' toes by circumventing them in their enthusiasm to get the Where the Wild Things Are project into motion.

After being fired, and feeling glum knowing his employment with Disney was to end shortly,[33]: 40  Lasseter visited a computer graphics conference in November 1983 at the Queen Mary in Long Beach, where he met and talked to Catmull again.

[17][33]: 40  From his experience at Lucasfilm, Catmull assumed Lasseter was simply between projects since Hollywood studios have traditionally laid off employees when they lack enough productions to keep them busy.

[35]: 45  Lasseter agreed instantly to work freelance with Catmull and his colleagues and joined them for a week of December 1983 on a project that resulted in their first computer-animated short: The Adventures of André & Wally B., meant to prove it was possible to do character animation on a computer.

[23] Lasseter spent a lot of time at Lucasfilm in the San Francisco Bay Area in the spring of 1984, where he worked together closely with Catmull and his team of computer science researchers.

[17] After the short CGI film was presented at SIGGRAPH in the summer of 1984, Lasseter returned to Los Angeles with the hope of directing The Brave Little Toaster at Hyperion Pictures.

[33]: 45  Catmull called back with a job offer, and Lasseter joined Lucasfilm as a full-time employee in October 1984 and moved to the Bay Area.

[33]: 45  After that, he worked with ILM on the special effects on Young Sherlock Holmes,[38] where he made the first fully computer-generated photorealistic animated character, a knight composed of elements from a stained glass window.

[39] Lasseter and Catmull's collaboration, which has since lasted over thirty years, would ultimately result in Toy Story (1995), which was the first-ever computer-animated feature film.

[45] Lasseter was so deeply moved that in 1985 he insisted on showing that clip and other examples of Miyazaki's work after dinner to a woman he had just met (who would become his wife).

Lasseter is a member of the Academy of Motion Picture Arts and Sciences and served nine consecutive years on its board of governors from 2005 to 2014 when he had to relinquish his seat due to term limits.

[47] In November 2017, Lasseter took a six-month leave of absence after acknowledging allegations of workplace sexual misconduct that he described as "missteps" with employees in a memo to staff.

[9] The alleged sexual misconduct toward multiple employees over a number of years included "grabbing, kissing, [and] making comments about physical attributes".

[1][50] In a statement, Lasseter said "I have spent the last year away from the industry in deep reflection, learning how my actions unintentionally made colleagues uncomfortable, which I deeply regret and apologize for.

[52] Lasseter lives in Glen Ellen, California, with his wife Nancy, a graduate of Carnegie Mellon University, whom he met at a computer graphics conference in San Francisco in 1985.