This cross-sectional study aimed to assess health providers' reported knowledge and practice competence regarding management of reproductive tract infections (RTIs) including sexually transmitted infections (STIs) in Vientiane, Laos. All 272 health providers (medical doctors/assistants, midwives/nurses and drug sellers) working with RTI/STI patients in one urban and one rural district were invited to fill in a self-completed questionnaire including four written simulated case scenarios, and 93% participated in the study. Of 252 respondents, 34% scored below 50% regarding both the case scenarios and reported knowledge, and 87% gave inadequate advice regarding health education. Only 34% gave correct advice on contact tracing, 38% on counselling, 52% regarding compliance and 59% on condom promotion. Drug sellers scored lowest in all aspects of RTI/STI management. Urban respondents were more likely to report adequate knowledge. Continuous training in syndromic approach and supervision are recommended to improve the quality of RTI/STI management, particularly at private pharmacies and in rural areas.