Joan Ruth (born c. 1904) was an American soprano and stage actress. Born in Massachusetts, she studied singing at the New England Conservatory and with Estelle Liebling in New York City. She had an active stage career in operas, concerts, and musicals from the early 1920s into the mid 1940s. She made her professional opera debut with the Wagnerian Opera Company in 1923. She sang two seasons with the Metropolitan Opera, and also performed roles with other American opera companies like the Cincinnati Opera and the St. Louis Municipal Opera. In 1926 she toured throughout the United States in concert with the tenor Edward Johnson. In 1927 she created the role of Sally Negly in the original Broadway production of Sigmund Romberg's My Maryland. She starred in the 1929 Warner Bros. short film Guido Ciccolini and Eric Zardo. She was also active as a singer on American radio stations in New York City.