Improved understanding of cholesterol levels in HIV- and hepatitis C virus (HCV)-infected persons in Argentina will guide optimal antiretroviral therapy. The authors conducted a cross-sectional study in Argentina to describe associations between HIV, HCV, and cholesterol. Of the 202 participants, 21 were HIV infected, 15 were HCV infected, 46 were HIV/HCV coinfected, and 120 were HIV/HCV uninfected. HIV/HCV-uninfected participants had the highest total cholesterol (TC) and low-density lipoprotein (LDL) levels. Multivariate modeling revealed that HIV/HCV-coinfected patients had the lowest TC levels (–28.7 mg/dL, P < .001) compared to the HIV/HCV-uninfected reference group. Hepatitis C virus and HIV/HCV coinfection were associated with lower LDL levels (–21.4 mg/dL, P = .001 and –20.3 mg/dL, P < .0001, respectively). HIV and HIV/HCV coinfection, but not HCV alone, were associated with lower high-density lipoprotein levels (–9.1 mg/dL, P = .0008 and –6.8 mg/dL, P = .0006, respectively). Further study is needed to examine whether the more favorable lipid profile observed in HIV/HCV-coinfected persons is associated with a reduction in cardiovascular risk.