Wister graduated from Harvard in 1882 and studied musical composition in Paris for two years. Ill health forced his return to the United States, and he spent the summer of 1885 in Wyoming. In the fall Wister entered Harvard Law School, graduating in 1888, and after being admitted to the bar in 1889, he practiced for two years in Philadelphia. He continued to spend his summers in the West, and in 1891, after the enthusiastic acceptance by Harper's of two of his western sketches, he devoted himself to a literary career.

The Virginian was the story of a cowboy ranch foreman and was a great popular success. It introduced such themes as the conflict of its genteel heroine, a schoolteacher from the East, with her cowboy lover, who depends for his life on a harsh code of ethics. Its climactic gun duel is considered the first such “showdown” in fiction. Wister's other major work was Roosevelt: The Story of a Friendship, 1880–1919 (1930), detailing his long acquaintance with Theodore Roosevelt, a Harvard classmate. Wister also wrote a number of books for children. His collected writings were published in 11 volumes in 1928. His journals and letters from 1885 to 1895 were published in Owen Wister Out West (1958), edited by his daughter, Fanny Kemble Wister.