Objective: The purpose of the present study was to examine the changes in the body perception of young children using a short-term longitudinal design, then to investigate the factors related to their body perception. Methods: Participants were 65 preschool children and their mothers that were recruited from five institutions. An 11-month, two-time point longitudinal design was used in which children were interviewed individually to examine the changes in body perception. At the second time point, children were assessed with an additional measure to investigate self-esteem, and their mothers also reported on maternal factors and children's media experience through a questionnaire. Data were analyzed by paired t-test, independent t-test, correlations and ANOVA. Results: The results showed a significant decline of children's negative body perception over time. Children’s media experience was positively correlated with negative body perception. Mothers whose children showed higher body mass index (BMI) sent more verbal messages about their child's weight reduction. In addition, children's negative body perception was positively correlated with physical self-esteem. Finally, there was a significant difference in only the physical self-esteem according to the level of children's body perception. Conclusion/Implications: The findings would suggest theoretical and practical implications to support intervention and education programs to improve the body image of young children.