Only about 85% of men who have sex with men (MSM) with HIV have been tested for and diagnosed with HIV. Racial/ethnic disparities in HIV risk and HIV care outcomes exist within MSM. We examined racial/ethnic disparities in delayed HIV diagnosis MSM. Males aged ≥13 reported to the Florida Enhanced HIV/AIDS Reporting System 2000–2014 with a reported HIV transmission mode of MSM were analyzed. We defined delayed HIV diagnosis as an AIDS diagnosis within three months of the HIV diagnosis. Multilevel logistic regressions were used to estimate adjusted odds ratios (aOR). Of 39,301 MSM, 27% were diagnosed late. After controlling for individual factors, neighborhood socioeconomic status, and rural-urban residence, non-Latino Black MSM had higher odds of delayed diagnosis compared with non-Latino White MSM (aOR 1.15, 95% confidence interval [CI] 1.08–1.23). Foreign birth compared with US birth was a risk factor for Black MSM (aOR 1.27, 95% CI 1.12–1.44), but a protective factor for White MSM (aOR 0.77, 95% CI 0.68–0.87). Rural residence was a risk for Black MSM (aOR 1.79, 95% CI 1.36–2.35) and Latino MSM (aOR 1.87, 95% CI 1.24–2.84), but not for White MSM (aOR 1.26, 95% CI 0.99–1.60). HIV testing barriers particularly affect non-Latino Black MSM. Social and/or structural barriers to testing in rural communities may be significantly contributing to delayed HIV diagnosis among minority MSM.