Introduction: Schoolbag weight across different types of school and schoolbag content has not been studied in Malaysia.This cross sectional survey determines the weight of schoolbags, its content and occurence of back pain among primary school children in different medium primary school in Kuala Lumpur.Methods: Students' body weight, and schoolbags weight were measured using a calibrated scale. Schoolbag content was examined, and weighed according to necessary learning materials or unnecessary materials. Back pain in the past one week was assessed using a self-administered questionnaire, adapted from previous studies. Results: A total of 358 students (167 male, 191 female) were enrolled, of which 119 were from National School (NS), 122 from Chinese Medium School (CMS) and 117from Tamil Medium School (TMS). The mean schoolbag weight was 4.55 ± 1.62kg for NS, 8.53 ± 1.94kg for CMS and 6.06 ± 2.09kg for TMS, which was 11.7%, 22.0% and 16.6% of body weight, respectively. The mean weight of unnecessary schoolbag content was 0.64(0.91)kg for NS, 2.18 (1.49) kg for CMS and 1.96(1.56) for TMS students. Back pain was detected in 87.0% NS students, 68.0% CMS students and 66.7% TMS students. Significant asociation was found between occurence of back pain and types of school (X²=16.64,p=0.00). Conclusions: Students from all the three mediums primary school, in particular Chinese medium school carry school bag heavier than that generally recommended, with unnecessary materials weigh up to 2kg. The occurence of back pain is high and this is associated with the types of school.