During the last decade, the incidence of male urethritis stopped declining in France. Risk factors associated with unprotected intercourse have been extensively studied in men who have sex with men, but not in men in general. The purpose of the study was to determine major risk factors for urethritis among men and to describe the sociodemographic and medical characteristics of this population in 2005. We conducted a prospective case-crossover study of sexual behaviors among men with acute urethritis attending at general practitioners or sexually transmitted infection (STI) clinics in France. Each patient filled out a selfcompleted questionnaire focusing on sociodemographic characteristics, and on sexual behaviors for the month before urethritis onset and for the preceding 3 months. The doctor reported medical information on a separate questionnaire. Between January and September 2005, 121 cases of male urethritis, defined as recent-onset pain on micturition and/or purulent or mucoid discharge, were included. Median age was 33 years, 22.3% were MSM, 55.1% were single, and 72.0% had at least high school education. Conditional logistic regression analysis showed that intercourse with only casual partners or with both casual and steady partners (OR = 2.6, CI 95%: 0.8-8.7, and OR = 8.7, CI 95%: 2.7-28.0), as well as inconsistent condom use (OR = 5.8, CI 95%: 1.7-19.2) significantly increased the risk of male urethritis. STI prevention campaigns should continue to focus on consistent condom use and should not neglect men over 30 years of age.