BACKGROUND Sleep is a natural requirement of human body. In adolescents, duration of adequate sleep is 8-10 hours. Sleep deprivation has many harmful consequences on health and academic performances among adolescents. Therefore, it is important to know the prevalence of sleep deprivation and identify the preventable modifiable risk factors causing insufficient sleep. The aim is to study the prevalence of sleep deprivation and to study sociodemographic, academic and other factors affecting sleep quantity during schooldays. MATERIALS AND METHODS A cross-sectional study was conducted among students of VIII, IX, X standard of two randomly selected schools. The data was collected using a pretested, semi-structured, self-administered questionnaire. RESULTS The average sleep duration was less than 8 hours on school days. Prevalence of sleep deprivation in students was 78.75% during schooldays. Among the enrolled adolescent students, female students were more sleep deprived than male students. Academic workload was the primary reason for sleep deprivation for most of the students. The multivariate analysis revealed a statistically significant association between sleep deprivation factors like age, mother's education and participation in sports by students. Computer use for >2 hours was associated with increased odds of sleep deprivation. CONCLUSION The duration of watching television or using internet must be restricted to the minimum, proper time management for academics and sports may help adolescents get adequate sleep. Also educating mothers about the importance of adequate sleep in children and measures for the same is important to reduce sleep deprivation among children.