Robert C. Plater (May 13, 1914, Newark, New Jersey - November 20, 1982, Lake Tahoe) was an American jazz alto saxophonist.

Plater began playing alto sax at age 12, and played locally in Newark with Donald Lambert and the Savoy Dictators in the 1930s. He played with Tiny Bradshaw from 1940 to 1942 before spending 1942-45 serving in the U.S. military during World War II. After his discharge he worked briefly with Cootie Williams, then played intermittently with Lionel Hampton between 1946 and 1964. He also did arrangements with Hampton, and did some freelance work besides. In 1964 he took Frank Wess's place in the Count Basie Orchestra, where he played until his death in 1982. His only recordings as a leader were four songs for Bullet Records in 1950.

Plater was the co-composer of "Jersey Bounce", a popular dance number in the 1940s, recorded by various musicians including Glenn Miller and Ella Fitzgerald.