Abstract: Objective To explore the status and correlated factors of sleeping among the children aged 2 to 7 years in Lanzhou city.Methods A questionnaire survey was conducted among the parents of 649 children selected with stratified random sampling from four urban districts of Lanzhou.Results The sleeping times decreased with the growth of the children(F=23.99,P<0.01).The total sleeping time of the children was less than that reported by domestic and international studies.The influencing factors of the children's total sleep time included children's age,sleeping habit and problems,and total sleep time and sleeplessness of the fosterer.The prevalence rate of sleep disorders was 50.7% in the children.The prevalence rate was 47.3% in the boys and 55.2% in the girls(χ²=3.987,P=0.046).The main influencing factors of sleeping were bad marrige status of parents,with single parent family,irregular sleep,sleep with parents,sleep disorder and educational background of the fosterer.Conclusion The total sleep time is at a low level and there is a high prevalence rate of sleep disorders among the children aged 2-7 years in Lanzhou city.The main influencing factors of the sleeping are family environment and sleep habit of the child and the fosterer.