OBJECTIVE To identify the frequency of syncope in a sample of women regular residents of Mexico City. METHODS Two hundred and twenty one women between 18 and 88 years old with voluntary participation were included in the study. Trained interviewers through a structured questionnaire obtained syncope information. Prevalence of syncope was obtained, and it's relation with: age, time since the last syncope and frequency of syncope in their live span was registered. RESULTS Thirty eight percent informed they had suffered syncope, of them 50% had only one syncopal episode during their lives. The others had two or more episodes. Most women had their last syncope between 19 and 50 years of age. CONCLUSIONS The frequency of syncope was a little higher than previous studies. This is a first approximation, which must be corroborated with larger studies with well population variability representation.