Although the field of gangs is well studied, information regarding the way gangs may use or misuse music for different needs is sparse. The aim of this systematic review is to gather descriptive and empirical information to ascertain the important roles rap music possesses within gang life. This review suggests five main functions of rap used within gangs with an emphasis on the subgenre of gangsta rap. First, rap facilitates antisocial behavior by reinforcing such messages in its lyrics. Second, its deviant lyrics serve as a reflection of the violent reality experienced in many urban ghetto communities. Third, it operates as a means for constructing individual and collective identity, as well as resistance identity. Fourth, it functions as an educating force by teaching its members how to act and respond in the urban ghetto. Finally, rap glorifies gang norms among newcomers and successfully spreads its values to the general population.