Neal Leon Cassady (February 8, 1926 – February 4, 1968) was a major figure of the Beat Generation of the 1950s and the psychedelic and counterculture movements of the 1960s. He was prominently featured as himself in the original "scroll" (first draft) version of Jack Kerouac's novel On the Road. He also served as the model for the character Dean Moriarty in the 1957 version of that book. In many of Kerouac's later books, Cassady is represented by the character Cody Pomeray.

In October 1945, after being released from prison, Cassady married the 16-year-old LuAnne Henderson. In 1946, the couple traveled to New York City to visit their friend, Hal Chase, another protégé of Brierly's. It was while visiting Chase at Columbia University that Cassady met Jack Kerouac and Allen Ginsberg. Although Cassady did not attend Columbia, he soon became friends with them and their acquaintances, some of whom later became members of the Beat Generation. While in New York, Cassady persuaded Kerouac to teach him to write fiction. Cassady's second wife, Carolyn, has stated that, "Neal, having been raised in the slums of Denver amongst the world's lost men, was determined to make more of himself, to become somebody, to be worthy and respected. His genius mind absorbed every book he could find, whether literature, philosophy or science. Jack had had a formal education, which Neal envied, but intellectually he was more than a match for Jack, and they enjoyed long discussions on every subject."

During 1964, Cassady served as the main driver of the bus named Furthur on the iconic first half of the journey from San Francisco to New York, which was immortalized by Tom Wolfe's book, The Electric Kool-Aid Acid Test (1968). Cassady appears at length in a documentary film about the Merry Pranksters and their cross-country trip, Magic Trip (August 4, 2011), directed by Alex Gibney.