Background: Primary dysmenorrhea is the most common gynecologic compliant among rnadolescent females. There is a wide variation in the estimate of primary dysmenorrhea 50 to rn90%. The disorder is the most common cause of short term school and class absenteeism, loss of rnclass concentration and test taking skill by adolescent women. rnObjective: To assess associated risk factors of primary dysmenorrhea and its effect on student’s rnacademic performance in Debre Berhan University, North shoa zone, Amhara regional state from rnSeptember 2011- May 2012. rnMethods: A cross-sectional study was conducted in Debre Berhan University from September rn2011 to May 2012 using multistage stratified sampling technique to select 440 female students. rnA structured and pretested self-administered questionnaire was used for data collection. The rnseverity of dysmenorrheal pain was assessed by using verbal multidimensional scoring system rnand visual analog scale (VAS). The data was double entered into Epi Info version 3.1 and rnanalyzed by using SPSS version 17. Data were analyzed using Xrn2rn test and logistic regression rnanalysis. P-value