Lester Young, nicknamed "Prez" (August 27, 1909-March 15, 1959) was an United States jazz tenor saxophonist.

Lester Willis Young was born in Woodville, Mississippi and grew up in a prominent musical family. His brother Lee Young was a noted drummer, and several other relatives played music professionally. His family moved to New Orleans, Louisiana when Lester was an infant. His father taught him to play trumpet, violin, and drums in addition to the saxophone. He left the family band in 1927 because he refused to tour in the US South, where the Jim Crow Laws were in effect.

He rose to prominence in the 1930s, playing in a relaxed style which contrasted sharply with the aggressive approach of Coleman Hawkins, the dominant tenor player of the day. In fact, after he left Count Basie's band to replace Hawkins in Fletcher Henderson's band, his style annoyed Henderson's sidemen so much that he soon left to play with Andy Kirk. He later returned to star with Basie.

Since Jazz already had a "King of Swing" with Benny Goodman, a "Duke" Ellington, and a "Count" Basie, Lester Young was known as Pres (short for "president"), a name given him by Billie Holiday. He returned the favor by dubbing her "Lady Day."

Young switched to bebop in the 1940s. However, after World War II he began to suffer from mental problems and alcoholism, often attributed to racist mistreatment he received during the war in the American military, but he maintained a high standard of performance. He is generally considered to be one of the greatest of jazz musicians.

Lester Young died in New York City.