Objective: To investigate the correlation of lifestyle with obesity among migrant children in Shanghai and to provide reference for preventing and controlling obesity of the migrant children. Methods: Stratified cluster sampling was adopted to conduct a routine physical examination and investigate lifestyle among 3 894 students (7-13 years old) in June 2018. Association of lifestyle with obesity was analyzed. Chi-square test was used to compare differences in obesity prevalence among migrant children with different lifestyles. Logistic regression was used to explore association with lifestyle and obesity. Results: Chi-square test showed that obesity rate in males (18.6%) was significantly higher than that of females(10.7%)(χ2=24.79, P<0.01). Sleep duration, screen time, exercise frequency correlated with obesity(χ2=35.13, 9.29, 7.98, P<0.05). Regression results illustrated that insufficient sleep duration associated higher risk of obesity, the odds ratio for obesity was (OR=2.61, 95%CI=1.64-4.11) and (OR=1.54, 95%CI=1.27-1.86) among children with sleep duration less than 6 h/d and 6-8 h/d, compared with children with more than 8 h/d sleep time, after multiple covariates controlled. Conclusion Sleep deprivation positively associated with obesity, ensuring adequate sleep time might help prevent obesity among migrant children.