Abstract: Toni Morrison's Beloved is studied here from the perspective of post-colonial feminism. By discussing the miserable fate of black females under sexism and racism, analyzing their marginalized state-living without identity or human rights, and exploring Morrison's thoughts on the identity construction of black females, the thesis demonstrates the writer's idea that black females could be rid of the double oppression from racism and sexism only when their history would be rewritten, their self-awareness aroused, their selfhood returned and their self-identity reconstructed.