Toni Morrison is a famous contemporary American writer who mainly focuses her attention on the life of the black: their history as well as their spiritual world. In her highly acclaimed novel Beloved, Morrison conciously sets African Americans’s past and their present living situation into her work, for she intends to make use of her literary discourse to reproduce “A New History”—the true history of the American black people that was once veiled by the American white’s mainstream society. In this way, she hopes to cure the psychological trauma of the black and call on her people to look for their lost culture root and reconstruct their ethnic consciousness. So this article will apply the theory of new historicism to analyze how Morrison reveals the pathetic history of American black and the cracks in colonialism and hegemony in Beloved, thus subverting the master discourse and breaking down the black’s marginalized identity,and finally reconstructing Afro-American’s culture and their subjectivity.