Objective: To analyze the association between maternal bisphenol A exposure during early pregnancy and sleep problems among preschool children. Methods: Research subjects were from one of the sub-cohorts(Ma'anshan Cohort) of the China-Anhui Birth Cohort Study (C-ABCS) in Ma'anshan city. The basic situation of pregnant women and sleep information of preschool children were investigated. We selected preschool children whose mother's maternal serum bisphenol A concentrations of the first trimester had been already detected between December 2012 to Januray 2014. 1 259 pairs of mothers and children were included. The concentrations of bisphenol A exposure during early pregnancy were divided into low, medium and high exposure groups according to 25^th percentile (P₂₅) and 75^th percentile (P₇₅) levels. Multivariate multinomial logistic regression model was used to analyze the association between maternal bisphenol A exposure during early pregnancy and sleep-related problems in preschool children. Results: The P₅₀ (P₂₅-P₇₅) of serum bisphenol A exposure level during early pregnancy was 0.231 (0.106-0.512) ng/ml. The sleep-related problems scores of 1 259 preschool children were (16.43±3.82) points. The occasional sleep-related problems were detected about 47.8% (602 cases) and frequent sleep-related problems were detected about 18.3% (230 cases). After the adjustment of the confounding factors such as children's gender, age, BMI, sleep position (lying down, sleeping on one's back), the length of time to sleep and the length of sleep at night, in comparison with bisphenol A low exposure group, the OR (95%CI) value of preschool children with occasional sleep-related problems in maternal bisphenol A high exposure group during early pregnancy was 1.44 (1.01-2.06). After the gender stratification, the results showed that in comparison with bisphenol A low exposure group, the OR (95%CI) value of preschool girls with occasional sleep-related problems in maternal bisphenol A medium and high exposure group during early pregnancy were 1.61 (1.05-2.46) and 2.40 (1.42-4.04), respectively. The OR (95%CI) value of preschool girls with frequent sleep-related problems in maternal bisphenol A high exposure group during early pregnancy was 2.64 (1.34-5.17). However, in boys, there was no statistically significant association between maternal bisphenol A exposure during early pregnancy and sleep-related problems (P>0.05). Conclusion Maternal bisphenol A exposure during early pregnancy might be related to sleep-related problems in preschool children.