OBJECTIVES: To estimate the prevalence of genital ulcer and urethral discharge in Pweto, Democratic Republic of Congo, and to analyze the association between the estimated prevalence and age, marital status, profession, and number of sexual partners. METHODS: We performed a descriptive cross-sectional study through a survey conducted in May 2004 in a representative sample of 106 men in Pweto aged between 15 and 65 years old, with a precision of 9.5%. Questionnaire items about current or previous ulceration and urethral discharge where self-reported and referred to the previous year as of the date of the survey. To study the associations, crude and adjusted odds ratios (OR) were calculated using multivariate logistic regression. RESULTS: The prevalence was 39.6% (95% confidence interval [CI], 30-49) for urethral discharge and 33% (95%CI, 24-42) for genital ulcer. Soldiers were identified as a risk group independently of age, the number of sexual partners during the previous year, and marital status. The multivariate analysis showed an adjusted OR of 3.25 (95%CI, 1.10-9.95) (p < 0.05) for the frequency of urethral discharge in soldiers compared with other professions. CONCLUSIONS: The high prevalence of sexually transmitted infections in Pweto and the associated factors identified prompted the initiation of a controlled condom donation program for soldiers. In conflict situations with a high prevalence of sexually transmitted infections and lack of health services, humanitarian aid organizations should implement prevention activities focused on risk groups.