INTRODUCTION: This study was conducted to estimate sleep duration in Saudi elementary school children, sleep habits and practices that may affect it, and compare our results to published data in other societies. METHODS: Parents of elementary school children were surveyed regarding their children's bedtime, rise time, sleep duration at night and daytime nap duration during weekdays and weekends. A questionnaire inquiring about demographical data, specific sleep problems and habits, and home environment was completed by the parents. RESULTS: The study comprised 511 (50.5 percent) boys and 501 (49.5 percent) girls. During weekdays, bedtime for the whole group was 21.3 +/- 1.8 hours, rise time was 5.9 +/- 0.5 hours, total sleep time (TST) was 8.4 +/- 1.1 hours, and TST and nap was 9.98 +/- 1.3 hours. Multivariate analysis revealed that TST was affected by regularity of bedtime, mother's level of education, daytime naps, and the habits of watching television (TV) and playing computer games after 20.00 hours. CONCLUSION: Nighttime sleep duration is shorter in Saudi school children compared to published datSeveral factors appeared to affect sleep duration, including mother's educational level, daytime naps and watching TV at night.