Men who have sex with men (MSM) are disproportionately impacted by the HIV/AIDS epidemic in the United States. The epidemic is not evenly distributed across MSM, and young racial minority MSM experience the highest rate of new infections. Race-based sexual stereotyping is not uncommon among MSM, and it may contribute to the isolation of racial minority sexual networks, which has been found to contribute to increased HIV incidence in Black MSM. The goals of these analyses were to describe the race-based sexual preferences and stereotypes of racially diverse young MSM (YMSM), and to examine whether endorsement of sexual stereotypes was associated with sexual risk behavior when having sex with partners of the stereotyped race. Data were taken from Crew 450, an ongoing longitudinal study of a syndemic of psychosocial health issues linked to HIV among YMSM in Chicago and surrounding areas. Analyses utilized data from three study waves, and longitudinal analyses were conducted with Hierarchical Linear Modeling. YMSM generally endorsed same-race preferences for sexual partners. Black partners were rated highest in displaying stereotypically dominant characteristics and in likelihood of taking the top/insertive sex role, while Latino partners were rated the highest in likelihood of sex being hot and passionate. White partners were rated lowest on each of these domains. Longitudinal analyses found that endorsement of these stereotypes had important implications for the rate of condomless receptive and insertive anal sex with racial minority partners. Findings suggest that sexual stereotypes may contribute to the isolation of racial minority sexual networks.