Background: Scabies is a contagious skin disorder and one of the most common itching dermatoses in whole of the world. Epidemiologic survey of scabies periodically done in many countries is a reflection of general status of public health in the community. Objective: To determine the prevalence of the scabies and its relationship with age, sex family size and place of residence. Patients & Methods: In this observational-cross sectional study on the students of primary schools in Somea-Sara in 2000-2001, 3656 students (On the basis of stratified random sampling) were selected and examined. The diagnosis of scabies was made on the basis of clinical criteria and the demographic data were recorded. Results: 50 out of 3656 students (1.36%) were suffered from scabies. The prevalence of scabies was 1.0% in urban schools and 1.61% in rural schools, 1% in male students and 1.7% in female students. The most common age group was 8-9 years and the mean of family size in patients was 6.1 and 6.2 in urban and rural areas, respectively. Conclusion: This study indicated that prevalence of scabies is higher in lower socio-economic state and larger family size.