The purpose of this study was to explore potential correlation between the amount of time children spent in child care centers and their daily stress levels. The subjects of this study were 165 children (aged 2~5) who attended a child care center in Seoul. Children were interviewed individually, and tested using 23 picture cards which describe a range of stressful situations. The results of this study were as follows: the children`s age led to significant differences in their stress level. The age at which the children first entered the child care center had no significant impact on their stress level. However, the times spent in child care centers showed a significant correlation with stress. The longer time the child spent in the center, the higher the degree of stress they encountered.