Elmer Kelton was born in Crane, Texas, in 1926. His father was the ranch foreman for the McElroy Ranch, where Kelton grew up. His mother was a schoolteacher, who taught him to read at the age of 5 or 6. He grew up around ranchers, ranchhands, bronc busters, and cowboys, and first started writing when he was 8 or 10 years old. He has said he always knew he wanted to be a fiction writer.

Encouraged by his high school English teacher at Crane High School, he attended the University of Texas, where he attended classes for 2 years before seeing combat infantry service in Europe during World War II. After the war, he returned to Texas with his Austrian-born wife, Anna, and returned to classes. He graduated from the University of Texas with a degree in journalism in 1948.

Kelton then got a job with the San Angelo Standard-Times as a farm and ranch writer. Later on, he became the agricultural editor, and after 15 years at the newspaper, he left to become editor of Sheep and Goat Raiser Magazine. He then went on to be associate editor of Livestock Weekly, a job he kept until 1990 when he retired. Throughout that time period, however, Kelton also wrote Western novels, selling his first stories to pulp magazines. He published his first novel in 1955, Hot Iron.

Since then, he has written roughly 40 novels, usually set in 19th Century Texas, based on stories he heard growing up around cowboys as a kid. Other novels have been based on historical events; his novel The Time It Never Rained, published in 1973, is based on a 7-year drought that occurred in Texas in the 1950s. Kelton's novels have won him seven Spur Awards, four Western Heritage Awards, and international acclaim. He is often praised for his characterization (while most people make their cowboys '7 feet tall and invincible', Kelton's are '5 foot 9 and nervous'), and his novels' abilities to capture the feel of West Texas as a region and a culture.

Western Writers of America have twice proclaimed him the most popular western writer of all time, ahead of Zane Grey, Willa Cather, Louis L'Amour and Pulitzer Prize winner Larry McMurtry. The Time It Never Rained has also won great praise, two major awards, and has been declared by John Tuska to be "one of the dozen or so best novels written by an American (in the 20th Century)". In 2003, San Angelo honored their most famous resident with a monument along the Concho River, near the art museum. Rather than a bust or statue of Kelton, it is instead a silhouette sculpture of a buffalo bull, cow, and calf grazing near a dry water hole.

Kelton lives in San Angelo, Texas with his wife, Anna. They have three grown children; Gary, Steven and Kathy.