We examined racial/ethnic differences in reported seroadaptive and serodisclosure behaviors among the partnerships of MSM recruited for a cross-sectional survey using time-location sampling (TLS) in San Francisco during 2007-2008. The sample (N = 1,199) consisted of 12.2% Asian/Pacific Islander (API), 52.4% White, 6.8% Black, 20.2% Latino, and 8.5% of "other" race/ethnicity. Pure serosorting was most common (about 20%) among HIV-negative men while seropositioning was most used (about 15%) by HIV-positive men. Reported seroadaptive behaviors did not differ significantly across races/ethnicities among both HIV-negative and HIV-positive men. However, HIV-positive Black and Latino men were significantly more likely to report no preventive, seroadaptive behavioral strategy (i.e., unprotected insertive anal intercourse with unknown status or serodiscordant partners). Among men who reported engaging in seroadaptive behaviors, they reported not discussing HIV status with a third of their partners-a major concern in that lack of disclosure undermines the effectiveness and means to practice serosorting. Partnerships of API and Black men were least likely to involve serodisclosure behaviors. Our study confirms that seroadaptive behaviors are common preventive strategies reported by MSM of all races/ethnicities, and does not find strong evidence that racial/ethnic differences in seroadaptive behaviors are enhancing disparities in HIV prevalence. The implications are that condom promotion and safe sex messages are not the only prevention measures adopted by MSM and that public health professionals should be well aware of current trends within the MSM community in order to better assist HIV prevention efforts.