Ammons grew up on a tobacco farm near Whiteville, North Carolina, in the southeastern part of the state. He served in the U.S. Navy during World War II, stationed on board the U.S.S. Gunason, a battleship escort. After the war, Ammons attended Wake Forest University, majoring in biology. Graduating in 1949, he served as a principal and teacher at Hattaras Elementary School later that year and also married Phyllis Plumbo. He received an M.A. in English from the University of California, Berkeley.
In 1964, Ammons joined the faculty of Cornell University, eventually becoming Goldwin Smith Professor of English and Poet in Residence. He retired from Cornell in 1998.
Ammons had been a longtime resident of Northfield, New Jersey, and Millville, New Jersey, when he wrote Corsons Inlet in 1962.