Ruth Hesse (18 September 1936 – 13 July 2024) was a German opera singer. A dramatic mezzo-soprano, she was a member of the Deutsche Oper Berlin from 1962 to 1995, where she took part in the world premiere of Henze's Der junge Lord. She was first invited to the Bayreuth Festival in 1960, where she performed until 1979.

Her international career began after she appeared at the Vienna State Opera in 1965 in two leading roles, Ortrud in Wagner Lohengrin and Eboli in Verdi's Don Carlos. She performed there regularly to 1988, and was appointed an Austrian Kammersängerin in 1982. Hesse first appeared as Brangäne in Wagner's Tristan und Isolde at the Opéra National de Lyon. Her first role at the Royal Opera House, in 1969, was the Nurse in Die Frau ohne Schatten by Richard Strauss, which became a signature role, repeated in Paris and at the 1974 Salzburg Festival, among others. Her voice was described as of a wide range, dark timbre and capable of dramatic expression.