Madeline Charlotte Moorman (November 18, 1933-November 8, 1991) was an American cellist and performance artist.

Moorman was born in Little Rock, Arkansas. She studied cello from age ten and won a scholarship to Centenary College (Shreveport, Louisiana) where she took her B.A. in music in 1955. She received her M.A. from the University of Texas at Austin and continued on to postgraduate studies at The Juilliard School in 1962.

She began a traditional concert hall career but was soon drawn into the active mixed-media performance art scene of the 1960s. She became a close associate and collaborator of Korean avant-garde artist Nam June Paik, with whom she toured widely. In 1963 she established the New York Avant Garde Festival which played annually in various locations including Central Park and the Staten Island Ferry until 1980 (except for the years 1970, 1976 and 1979).

In 1967 she achieved notoriety for her performance of Paik's Opera Sextronique, a seminude performance which resulted in her arrest on charges of indecent exposure; she was given a suspended sentence. The incident gave her nationwide fame as the "topless cellist." She also performed Paik's TV Bra for Living Sculpture (1969) with two small television receivers attached to her breasts. Another memorable piece was her performance of Jim McWilliams' Sky Kiss in many locations including New York and Sydney, Australia, which involved her hanging suspended from helium-filled weather balloons or the brightly-colored inflatable sculptures of Otto Piene.

As well as being a star performer of avant-garde pieces, she was an effective spokesperson and negotiator for advanced art, charming the bureaucracies of New York and other major cities into co-operating and providing facilities for controversial and challenging performances. The years of the Avant Garde Festival marked a period of unparalleled understanding and good relations between advanced artists and local authorities.

In the late 1970s Moorman was diagnosed with breast cancer. She underwent a mastectomy and further treatment, to continue performing through the 1980s in spite of pain and deteriorating health. She died of cancer in New York City on November 8, 1991, aged 57.

Charlotte Moorman was involved with the Fluxus movement of avant-garde and performance art and was a friend and associate of many well-known artists of the late twentieth century, including Nam June Paik, John Cage, Joseph Beuys, Yoko Ono, Carolee Schneemann, Jim McWilliams and others. In 1966 artist Joseph Beuys created his work Infiltration Homogen für Cello, a felt-covered violoncello, in her honor. Body artist Carolee Schneemann maintains a memorial page for Moorman on the Web.