Passing fits into many genres of literature, but it’s usually thought of as one of the most important novels in Black 20th-century psychological fiction. Larsen exposes Irene Redfield's inner world throughout the novel.
As is typical of this genre, the narrative focuses on Irene's experiences and the reasons behind her choices. Every action is examined and re-examined. By doing this, the narrator reveals Irene’s constant efforts to interpret the motivations of others, especially Clare Kendry and her husband Brian. Irene's intense internal monologue also exposes her insecurities around motherhood and safety. It also constantly surfaces contradictions in her feelings, such as her simultaneous attraction to and suspicion of Clare. Exploring Irene's psyche this way allows readers to understand how her perceptions and assumptions drive her actions.
The novel also falls into the related genre of social commentary literature. It offers a commentary on race, identity, class, and gender in early 20th-century America from a Black female perspective. Larsen examines the phenomenon of "passing" and its personal and societal implications: any "passing" in one’s life seems to make everything else black and white. The story shows how the rigid boundaries of segregation force people like Clare to navigate dangerous social terrain. They may embrace one aspect of their identity (for Clare, her perceived whiteness), but it comes at the cost of their authentic selves. Passing also addresses class distinctions within the Black community, illustrating how socioeconomic status, gender, and even colorism affect access to opportunities. Larsen looks particularly hard at the relationship between gender and Blackness, as her female characters contend with the limitations placed on them by marriage, motherhood, and perceived racial identity.