The prevalence of overweight among Chinese children under 5 years of age has been increasing steadily. Using data from China Health and Nutrition Survey (CHNS) spanning from 1991 to 2015, this study investigates the relationship between maternal employment status, maternal education level, and the prevalence of child overweight among Chinese children under 5 years old. The findings indicate that having mothers with low middle school education significantly reduces their children's body mass index z-scores (BMIZ) (p < 0.05). However, no significant association is observed between maternal education level and childhood overweight in urban areas. In rural areas, only when the maternal education level is college or above, there is a significant increase in BMIZ (p < 0.01). The impact of maternal education level on childhood obesity is influenced by household per capita income, and when household per capita income reaches a certain level, higher maternal education is negatively associated with child BMIZ. The study also reveals a significant negative association between maternal employment (p < 0.01),average weekly working days (p < 0.01), and the BMIZ of children under 5 years of age, while the interaction effect between them is positive and significant. This study has recommended some policy interventions, by promoting parental education on child feeding and parenting, providing professional child care, and offering financial subsidies to families with children under 5.