BACKGROUND: Urinary tract infections (UTIs) in elderly patients can be a complex problem in terms of approach to diagnosis, treatment, and prevention, because the patients often present nonspecific symptoms. The epidemiological and clinical characteristics of UTI in elderly women were studied, in order to make early diagnosis and prevent serious clinical complications secondary to UTI. METHODS: This was a prospective population-based study, with elderly women, during their first medical office visit. Medical records were obtained by clinical history and physical examination in order to detect signs and symptoms of UTI and the presence of comorbidities. Clean-catch midstream urine specimens for urinary dipstick test, sediment, and culture were collected; cervical samples for conventional Pap smears were also collected. RESULTS: UTI was found in 16.55% of elderly women. The most frequent urinary symptom was foul smelling urine, in 60.6%. E. coli was responsible for 98 (76.56%) cases of significant bacteriuria; 34 (34.69%) were resistant to trimethoprim-sulfamethoxazole, and 21 (21.42%) to fluoroquinolones. Asymptomatic bacteriuria (AB) was not treated. The presence of predisposing factors demonstrated that the history of previous UTI (p < 0.001), vaginitis (p < 0.001), and diabetes (p = 0.042) increased the risk for UTI. CONCLUSION: This study confirmed the high prevalence of UTI among elderly women and its unusual clinical presentation. Diabetes, history of previous UTI, and vaginitis were shown to be predisposing factors for UTI; it is not necessary to treat AB in elderly women, even among diabetics.