Objective: The purpose of this study was to determine the risk for urinary tract infection in women with or at risk for human immunodeficiency virus infection. Study Design: A prospective study of 871 women who were human immunodeficiency virus seropositive and 439 women who were human immunodeficiency virus seronegative was conducted, with additional semiannual interviews, human immunodeficiency virus serologic evaluation, human immunodeficiency viral load determination, T-cell subset test, urinalysis, pregnancy test, and selected quantitative urine culture examination. Results: At baseline, 26 women (3.0%) who were human immunodeficiency virus seropositive and 14 women (3.2%) who were human immunodeficiency virus seronegative women had urinary tract infections(P =.97). During 4280 person-years of follow-up, incident urinary tract infections was associated significantly with <12 years education (adjusted risk ratio, 1.43; 95% CI, 1.01-2.00), public assistance (adjusted risk ratio, 1.70; 95% CI, 1.11-2.60), pregnancy (adjusted risk ratio, 3.04; 95% CI, 2.04-4.53), and recent previous urinary tract infection (adjusted risk ratio, 1.82; 95% CI, 1.16-2.86), but not with human immunodeficiency virus infection. Among women who were human immunodeficiency virus seropositive, risk was associated with viral load (adjusted risk ratio, per log10 increase 1.30; 95% CI, 1.03-1.63), but not with CD4+ lymphocyte count. Conclusion: Risk for urinary tract infection is not associated with human immunodeficiency virus infection but is associated with viral load among women who are infected with human immunodeficiency virus. (Am J Obstet Gynecol 2002;187:581-8.)