Background: Dysmenorrhea is a pain associated with menstruation which can be relieved by applying different treatment approaches. It is a highly prevalent problem across the world. Even though, there are studies, full understanding of dysmenorrhea is very important for intervention. Objective: Therefore, the aim of this study was to determine the proportion of Dysmenorrhea, its associated factors and coping mechanism among secondary and preparatory school students in Bahir Dar city. Method: Institutional based Cross sectional study supported by qualitative study was conducted. For quantitative part, data was collected from 722 participants. All randomly selected students who were enrolled to school in 2021/2022 academic year were included in the study. Semi-structured self-administered questionnaire was prepared, and utilized. The collected data were analyzed by using Spss version 23 and Atlas Ti 7. Descriptive analysis like percentage and frequency distribution of the respondents was used. Bi-variable and multivariable logistic regression was used. For qualitative phenomenological design was used. Data was collected by in-depth interviews. Respondents were selected purposively. Interviews were audio-recorded and transcribed. Thematic analysis was done by using software Atlas Ti version 7. Results: The proportion of dysmenorrhea was found to be 79.6% (95% CI, 76.5% - 82.6%). In this study, about 120(16.1%) of the respondents with dysmenorrhea ignored their pain and only 69(9.8%) respondents visit clinic to consult health professionals. Family history of dysmenorrhea (AOD 1.810, [95% CI 1.199-2.733]), early menarche (AOD 2.195, [95% CI, 1.239-3.886] and urban residence (AOD 2.108, [95% CI, 1.208-3.680]) were found to be the predictors for the occurrence of dysmenorrhea. Conclusion & Recommendation: The proportion of dysmenorrhea was high. Residence, age at menarche, and family history of dysmenorrhea was found to be predictors of the occurrence of dysmenorrhea. Hot application, hot beverage and rest were the most common coping mechanisms of pain. Health Education about dysmenorrhea and its management options is important. Key words: Dysmenorrhea, Bahir Dar city, secondary and preparatory school students