Abstract: Black racial language discrimination experienced a long period of existence in American history. It seems that the black group always gives people the impression that their social, political and cultural status is very low. This seems to be imposed by white Americans on the black group, and the black group can only passively accept this identity setting. However, it should be pointed out that in many human rights movements, black people have tried to change this passive situation and construct their positive social identity, especially the recent anti-racial discrimination activities in the United States due to the death of a black man, George Floyd, caused by white policeman violence. Taking Green Book, the best film of the 2018 Oscar, as an example, this article links racial discrimination with identity construction, and analyzes how the hero, Dr. Shirley, actively constructs his identity as one of black group from the perspectives of equal right and civic right in his conversation with the southern white Americans.