"Floaters" are a large population of internal migrants in China. Led by a series of urban-based economic policies and the consequent income gap between rural and urban regions, these former peasants left their hometowns, floating temporarily and illegally in the cities for economic opportunities. Without legal immigration status, they are marginalized by local urbanites and are considered by the government as disobedient citizens with the potential to jeopardize the socialist society. This dissertation, drawing on two years' ethnographic and archival research in China, examines the basic characteristics of floaters' musical world and focuses on three representative musical components. The first is a repertory called Sour Songs, which originates from floaters' rural hometowns and serves as an outlet for release of nostalgia and spiritual pain. The second, Red Songs, is a genre invented by the communist government that has become an effective propaganda tool and is characterized as "a powerful bolt of the revolutionary machine" in the floaters' world. Finally, Rock 'n' Roll, the only musical form in China that signifies both urbanity and revolt, is used by floaters to display their special identity and to express themselves when they are silenced in the broader society. This dissertation reveals hidden meanings in floaters' music-making and suggests that the study of this overlooked musical community could provide new perspectives on Chinese music at large. / Music