This study is to survey the relationships between preschool experience and cooperation, competition of children. Also the study investigated whether the relationship vary due to a) grade level, b) geographical distribution such as urban school or rural school and c) sex of children. To investigate these problems, 240 children who attended a preschool program and 240 preschool who didn`t. They were randomly selected from first -, third-, and fifth grade of urban or rural elementary school children cooperative and competitive attitudes were assessed by the childrens self-report on the cooperation or competition questionnaire. The results of analysis showed the following: 1) preschool-experienced children were more cooperative, competitive and involving, and revealed less preference of competition than children who had no experience. 2) There was a significant relationship between the grade levels and cooperation, competition, involvement and preference of competition. Interaction between grade levels and preschool experience was not significant. 3) There were significant differences in cooperation, copetition, involvement, preference of competition, between urban school children and rural school children. whereas there was no difference in competition, No relationship was found between geographic) distribution and preschool experience of children. 4) Sex difference in competition was observed with girls being higher than boys. The results of the present study suggest that children who experienced a perschool program are more cooperative and less preference of competition than children who didn`t and there are significant differences in cooperation, copetition, involvement, preference of competition among children of different grades, and geographical distribution affects cooperation, involvement, preference of competition but not competition, only competition difference was observed between boys and girls.