Florence Helen Levin was born March 24, 1910 in Columbus, Ohio, the daughter of Samuel M. and Jennie (Klein) Levin. Levin had an early interest in music, winning competitions in concert piano in her teen-age years. She majored in music at Ohio State University, where she met, and in 1933 married, Samuel D. Lockshin. The couple had twin sons, Richard and Michael. After earning a B.S. in music in 1931, she continued to perform and was a founder of the Four Piano Quartet in Mansfield, Ohio. Most of Lockshin's early compositions were for the piano. She wrote and often arranged works to be played by the Quartet. In 1951, the Four Piano Quartet represented Ohio at the 26th Biennial Convention of the National Federation of Music Clubs.

In 1952, Lockshin moved to Northampton, Massachusetts, where she studied composition at Smith College (1952-55) under the tutelage of composer Alvin Etler. From this point, Lockshin turned her attention to larger ensembles, composing primarily for orchestra or chorus and orchestra. Her first such work was The Cycle (1956-57), a ballet commissioned by the Smith College Dance Department.

In 1959, Lockshin began to incorporate folk themes into her work in Annie Bradley's Tune, a piece based on a short melody sung to Lockshin's twin sons by their African-American nurse. Paean Santa Maria de Guadalupe (1962) is based on a hymn Lockshin heard penitents sing as they approached the basilica in Mexico City. When her husband's work as a management consultant took them to Arizona in the late 1960s, Lockshin's response to the music she heard there was the orchestral suite Scavarr (1969), based on Yuma and Mojave themes. After retirement, Samuel Lockshin worked for the International Executive Service Corps as a volunteer business consultant in Columbia, Venezuela, and Panama. ¡Cumbia! Fantasy on a Columbian Folk Dance (1977) was inspired by music heard during the Lockshins' many trips to various countries in Central and South America.

Interest in women composers spurred by the women's movement, plus interest in all things American connected with the country's bicentennial in 1976, led to a series of performances of Lockshin's work during the 1960s and 70s. Annie Bradley's Tune was the most-performed, both in the U.S. and in concerts of American music in Venezuela and Panama.

Florence Levin Lockshin died in Naples, Florida, on September 26, 1997.