Abstract Background C-reactive protein (CRP) is an inflammatory biomarker associated with all-cause mortality and morbidities such as cardiovascular disease. CRP is increased with HIV infection and thought to increase with age, though trajectories of CRP with aging have not been well characterized. We investigated trajectories of CRP in men from the Multicenter AIDS Cohort Study, according to HIV infection and HIV viral load status. Methods CRP measurements from 12 250 serum samples, provided by 2132 men over a span of 30 years, were categorized by HIV status at sample collection: HIV uninfected (HIV−, n = 1717), HIV infected with undetectable RNA (HIV+ suppressed, n = 4075), and detectable HIV RNA (HIV+ detectable, n = 6458). Age-related trajectories of CRP were fit to multivariable linear mixed models; we tested for differences in trajectories by HIV status. Results CRP increased with age in all sample groups. HIV+ detectable and HIV+ suppressed samples had higher CRP than HIV− samples throughout the observed age range of 20–70 years (p < .05). CRP concentrations at age 45 years were 38% (95% CI: 26%–50%) and 26% (15%–38%) higher in HIV+ detectable and HIV+ suppressed samples, respectively, relative to HIV− samples. HIV+ detectable samples showed more rapid linear increases with age (8% higher/decade, 0.3%–16%) than HIV− samples. Conclusions We observed higher concentrations of CRP across 5 decades of age in men living with HIV, and steeper increases with age in men with detectable HIV RNA, relative to HIV− men. These results are consistent with a contribution of inflammation to the higher risk of age-related comorbidities with HIV infection.