Protective response rates to hepatitis B (HB) vaccination have been reported as low as 18-62% in HIV-infected persons. The relative importance of various predictors for this poor response has not been fully characterized. In this retrospective cohort study, we examined the relationship between clinical characteristics and vaccine non-response (HB surface antibody <10 IU/L) among patients attending an urban HIV clinic. Among the 97 patients who met the inclusion criteria, 43 (44%) developed a protective antibody response. In multivariate analyses, age >40 years (odds ratio [OR] 3.03 [95% confidence interval [CI], 1.14-8.06]; P = 0.026) and alcohol abuse (OR 4.92 [95% CI, 1.72-20.89]; P = 0.007) were independent predictors of failure to develop vaccine response. In addition, CD4 nadir <200 (OR 7.24 [95% CI, 1.91-27.41]; P = 0.004), rather than CD4 current to vaccination, remained a strong independent risk factor. Patients with HIV viral suppression on highly active antiretroviral therapy had a significantly lower rate of vaccine failure (OR 0.31 [95% CI, 0.11-0.91]; P = 0.033), after adjusting for these other covariates. Our findings underscore the importance of confirming seroconversion after HB vaccination in HIV-infected patients and initiating vaccination early in the course of HIV infection.