Aim: To study the prevalence of scoliosis and its associated factors among male adolescents in Abha city intermediate and secondary schools, Aseer Region, Southwestern Saudi Arabia. Methods: Through a cross-sectional study, students were interviewed about personal and demographic data, method of back-bag carriage, and regular practice of any physical exercise. Body mass index (BMI) was measured and student’s bag weight/BMI ratio (%) was computed. Screening for scoliosis was performed using inspection of the vertebral column and Adam’s Forward Bending Test (FBT). Using scolimeter a reading equal or exceed 5 degrees was considered positive. Results: Out of 417 screened adolescents, 90 students were positive giving a prevalence rate of scoliosis of 19.1% (95% CI: 15.7- 23.0). Using multivariable logistic regression analysis, the probability of positive scoliosis was significantly higher in secondary school (aOR=2.304. 95% CI: 1.447-3.676) and obese and overweight (aOR=2.433. 95% CI: 1.565-3.787) adolescents. On the other hand, regular practicing of physical exercises was significantly negatively associated with scoliosis (aOR=0.469, 95% CI: -316-0.695). Conclusion: The present study identified scoliosis as a substantial problem among adolescents. School health authorities need to foster a screening program for scoliosis, particularly among secondary school adolescents. School health promotion programs should address overweight and promote physical exercise to deal with this problem.