Warne Marion Marsh (October 26, 1927 – December 18, 1987) was an American tenor saxophonist. Born in Los Angeles, his playing first came to prominence in the 1950s as a protégé of pianist Lennie Tristano and earned attention in the 1970s as a member of Supersax.

Marsh came from an affluent artistic background: his father was Hollywood cinematographer Oliver T. Marsh (1892–1941), and his mother Elizabeth was a violinist. He was the nephew of actresses Mae Marsh and Marguerite Marsh and film editor Frances Marsh.

He was tutored by Lennie Tristano. Marsh was often recorded in the company of other Cool School musicians, and remained one of the most faithful to the Tristano philosophy of improvisation – the faith in the purity of the long line, the avoidance of licks and emotional chain-pulling, the concentration on endlessly mining the same small body of jazz standards. While Marsh was a generally cool-toned player, the critic Scott Yanow notes that Marsh played with “more fire than one would expect” in certain contexts.