Objective: The gold of this study is to identify the correlation between mothers’ rejective parenting attitude and children’s humanity and adaptation to educational institutions, as well as to find out whether children’s humanity could act as a mediating effect against mothers’ rejective parenting attitude in the process of children’s adapting to the institutions. Methods: The study was conducted on 259 children aged 4 to 5 and their mothers. The collected data were used to conduct Pearson correlation coefficient, Three-step mediated regression analysis, and the Sobel test using the SPSS 20.0 program. Results: First, children’s institutional adaptability had a significant negative correlation only with ‘mother’s hostility’. Children’s humanity had a significant positive correlation with their institutional adaptability. Second, mothers’ hostile attitude had a direct or indirect impact on children’s institutional adaptability. Conclusion/Implications: The results above suggest that children’s good humanity and parents’ friendly attitude are important in children’s institutional adaptability.