Abstract: ObjectiveTo investigate the sleep status of preschool children in Shanghai, and analyze the common sleep problems of preschool children with different characteristics. MethodsAccording to the principle of universal mobilization and voluntary participation, kindergartens in Songjiang district of Shanghai were chosen as the scene of questionnaire survey, and the questionnaire of children's family social environment and sleep health was used as a survey tool. Analysis was by age and stratified gender. Sleep problems include sleep deficiency，sleep delay，and the occurrence of sleep disorder more than twice a week during sleep like fear of going to bed, snoring, excessive daytime sleepiness, molars, night terrors, nightmare, difficulty falling asleep and sleepwalking. First of all, the kindergarten health care teachers received the centralized and unified training, and then the kindergarten health care teachers trained the class teachers. The questionnaire was filled in by the father or mother of the child, or the relatives who raised the child and lived with the child for nearly one year. The class teachers sent out questionnaires, which filled in and collected on the spot. ResultsFrom May to June 2018, 22 kindergartens participated in the questionnaire survey, 8,624 questionnaires were sent to parents and 8,586 valid questionnaires include 4 595 boys(53.5%) and 3 991 girls(46.5) with 17.8% in the 3-year-old group, 34.1% in the 4-year-old group, 32.0% in the 5-year-old group and 16.1% in the 6-year-old group. The average time of going to bed at night was 21∶43, and the average time of waking up in the morning was 7∶01. The total sleep time, daytime sleep time and nighttime sleep time decreased with the growing age, and the average time of going to bed at night was delayed, and the average time of waking up in the morning was advanced. The difference was statistically significant (P<0.01). There were no significant differences in the daytime sleep time, nighttime sleep time, total sleep time and bedtime in preschool children of different genders (P>0.05). The incidence of sleep deprivation was 12.2%, and the incidence of sleep delay was 75.7%. The incidence of sleep deprivation and sleep delay were decreasing with the growing age, and the difference was statistically significant (P<0.01). The incidence of fear of going to bed was 72.4%, snoring was 62.5%, excessive daytime sleepiness was 51.2%, molars was 50.4%, night terrors was 49.2%, nightmare was 41.2%, difficulty falling asleep was 33.4% and sleepwalking was 4.4%. The incidence of snoring and molars in boys was significantly higher than that in girls (P＜0.05), while the incidence of night terrors, nightmares, difficulty of falling asleep and sleepwalking in girls was significantly higher than that in boys (P＜0.05). ConclusionThe incidence of sleep deficiencies, sleep delay and sleep problems are higher of preschool children in Songjiang district of Shanghai, which should be paid attention to by the society and parents.