This study examines the impact of the deviation between parents' educational expectations and children's educational expectations on children's health. This study based on the data from Chinese Family Panel Studies conducted in 2018 and 2020, The participants were 2340 children aged 10-15 years (1310 boys, 1030 girls) in China. We found that when parents' educational expectations are higher than their children's educational expectations, they have a negative impact on children's health status. According to the influence mechanism, the higher the parents' expectations of education are, the greater children's remedial behaviour will be, the less leisure time will be, which will adversely affect children's health. Furthermore, we found that a good parent-child relationship moderated the negative impact of the deviation in parent-child educational expectations on children's health. Therefore, in order to ensure the healthy development of children, it is necessary to resolve the adverse effects of the deviation in parent-child educational expectations by arranging tutoring and leisure time rationally and establishing a good parent-child relationship.