Purpose: The research was to identify menstrual regularity & mental health-related factors on unmarried women of childbearing age and provide a raw material in terms of setting up health policy. Methods: The KNHANE V-3 (The Fifth Korea National Health and Nutrition Examination Survey) was used and implemented through spss 18.0. Results: In general characteristics, there wasn't any remarkable difference between 20s and 30s. Looking further Mental health-related factors, stress was higher in 30s (p=.010). In 30s of irregularity mensutration women, it was accounted for 12.5% over than 3months experienced. General characteristics varied by menstrual regularity were age (p=.044), education level (p=.035) and in terms of mental health-related factors, they were stress (p=.044), sleeping time (p=.039). Multiple regression analysis was carried out to identify how influential these factors are on menstrual regularity. As a result, age, education level, sleeping time & stress was the most influence factors. Conclusion: The research had some limitations to specify and approach the feature of target in depth through KNHANE V-3. Thus, if the basic analysis regarding the menstrual problem in relation to local society was conducted on the basis of the result of research, it could help developing the promotion of health program and make the application easier.