In the twentieth century people had to live in a world of migration. According to Philip L. Hammack the borders were not solid in the modern world and identity is a matter of sameness and difference adding that the self shows itself to the outer world through identity. Jean Rhys, in “Voyage in the Dark” tells Anna Morgan’s story in a postcolonial world in modernist words and emhasizes the importance of identity as a sociological and cultural concept. Anna’s identity problem as a female is very related with the fact that she has to move from her Caribbean home to England after his father’s death by the influence of her step-mother. As the protogonist of the novel Anna is portrayed as a kind of de-centered modernist subject with her fragmented cultural identity. Anna’s identity is shaped with varied voices as a cross-cultural identity, and it is seen that she suffers from her in-betweenness throughout the novel. In the study, identity problem of the modern individual having multiple identities and roles as being the members of multiple groups and social and cultural backgrounds in British society has been analyzed in order to show the dilemma of the fragmented and alienated identities with references to modernism in a interdisciplinarity perpective.