The present study was done to assess the prevalence of Premenstrual Syndrome (PMS) among girls, to identify the severity of PMS, to assess the knowledge regarding PMS and its management, to find the association between prevalence of PMS and selected socio-demographic variables, menstrual details and Body Mass Index (BMI) and determine the association between knowledge regarding PMS and its management and selected socio-demographic variables. The sample consisted of 100 girls who have attained menarche of age group 18-20 years by convenience sampling technique. The design used was descriptive survey design with quantitative approach. The tools used were structured questionnaire for socio-demographic, menstrual details and knowledge regarding PMS and its management. Biophysical variable was assessed by the investigator herself and four point rating scale was used to assess prevalence and severity of PMS. The findings of the present study were that the prevalence of PMS was 73% among the girls based on the American College of Obstetrician and Gynaecologist (ACOG) diagnostic criteria. More than half (69.86%) of the samples have moderate PMS. About 88% of the samples had average knowledge, 9% had poor knowledge and 3% had good knowledge regarding PMS and its management. There is significant association between prevalence of PMS with age in years (χ²=6.48, P<0.05) and there is significant association between level of knowledge regarding PMS and its management with monthly family income (χ²=15.956, P<0.05). Hence the study concluded that prevalence of PMS is 73%. Socio-demographic variables have an influence on prevalence of PMS and knowledge regarding PMS and its management.