OBJECTIVES: To establish incidence rates and risk factors for HIV-associated oral candidiasis (OC), oral hairy leukoplakia (OHL), and any HIV-associated oral diseases (HIV-OD). DESIGN: This prospective, cumulative case-control study followed 283 initially oral disease-free HIV-1-infected men and women for 2 years. Incidence rate ratios (IRR) and incidence proportions for OC, OHL, and HIV-OD were estimated. Multivariable analyses using Poisson regression determined the most parsimonious best-fitting model explaining the outcomes. RESULTS: Incidence rate (per 1000 person-months) was 9.3 for OC, 6.8 for OHL, and 13.5 for HIV-OD. Incidence of OC was associated with low CD4 count (adjusted IRR = 3.0 (95% CI = 1.7, 5.1)), smoking (IRR = 1.9 (1.0, 3.8)) and combination antiretroviral therapy (IRR = 0.3 (0.1, 0.8)). Incidence of OHL was associated with low CD4 count, conditional upon smoking status. Conclusions Low CD4 count and smoking are important risk factors for HIV-associated OC and OHL. Antiretroviral medications are protective for OC but not for OHL.