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Lee Marvin was director Steven Spielberg's first choice for the role of Quint, despite his reservations about using big-name actors. Marvin thanked him but replied that he would rather go fishing. Spielberg then wanted Sterling Hayden for the role of Quint. Hayden, however, was in trouble with the Internal Revenue Service for unpaid tax. All of Hayden's income from acting was subject to a levy by the IRS, so there was an attempt to circumvent that; Hayden was also a writer, so one idea was to pay him union scale for his acting and buy a story from him (his literary income was not subject to levy) for a large sum. It was concluded that the IRS would see through this scheme, so Robert Shaw was cast by Spielberg instead on the recommendation of the film's producers, Zanuck and Brown.
Several decades after the film's release, Lee Fierro walked into a seafood restaurant and noticed an "Alex Kintner Sandwich" on the menu. She commented that she had played his mother many years ago. Jeffrey Voorhees, owner of the restaurant, ran out to meet her. He had played her son, and they hadn't seen each other since the original movie shoot.
According to director Steven Spielberg, the prop arm looked too fake in the scene where Chrissie's remains are discovered, so instead, they buried a female crew member in the sand with only her arm exposed.
When composer John Williams originally played the score for director Steven Spielberg, Spielberg laughed and said, "That's funny, John, really; but what did you really have in mind for the theme of Jaws?" Spielberg later stated that without Williams's score, the movie would only have been half as successful and according to Williams, it jump-started his career.
According to writer Carl Gottlieb, Roy Scheider ad-libbed the line "You're gonna need a bigger boat."
Over 67 million people in the U.S. went to see this film when it was initially released in 1975, making it the first summer "blockbuster."
Steven Spielberg: Voice on Quint's marine radio, when Mrs. Brody tries to contact her husband on the "Orca."