The scenes with Oliver walking alone through a snowy New York were added after principal photography was completed. The production was almost out of money and did not have the necessary funds for permits to shoot in New York City again - so all the shots were grabbed "illegally" using a skeleton film crew and Ryan O'Neal.
The most famous line from the film, "Love means never having to say you're sorry", was actually misspoken from the script. Originally the line was supposed to be: "Love means not ever having to say you're sorry."
John Wayne refused to believe that Love Story (1970) "sold because the girl went around saying 'shit' all the way through it." Instead he believed that "the American public wanted to see a little romantic story."
Both the Cornell and Dartmouth hockey teams were played by Dartmouth's actual team. Cornell hockey coach Ned Harkness only allowed Cornell jerseys to be used in the film, on the condition that Cornell win the game with Harvard.
Old-fashioned gas lights and lamp posts out of Boston's long past, from places like Beacon Hill, were added to scenes in Harvard Yard to make it look more like the producer's image of Harvard. Ryan O'Neal ruined several takes by tripping over the chains holding them in place.
Original director Larry Peerce, who had directed Ali MacGraw in her debut Goodbye, Columbus (1969), left the film during pre-production and Arthur Hiller came on board for 250,000 dollars plus 25 percent of the net. According to Peter Bart, who was then a young Paramount executive, this earned Hiller a further five million dollars.
It was the production of this film that led to Harvard University to prohibit almost all commercial filming on their campus, reportedly because of disruptions to students and damage to the campus, including fake snow killing several trees. The production was kicked off the campus after only a week of filming. Most subsequent films set at Harvard filmed at other nearby schools.