It is likely that the forms and nature of play will depend on the characteristics of children's toys. This study examined such characteristics, and related changes in preschool children's social behaviors to their sociability. Eight 5-year-old children (two boys and two grils with highest sociability: two boys and two girls with lowest sociability) were observed. They played in pairs (formed by same sociability level and gender), with eight different toys, and their behaviors were videotaped. The implications of these findings are that: (1) The theme of play and social behavior during play changed according to the characteristics of the different toys. For the girls, the popularity of the toy greatly influenced the interactions among them. (2) Interactions and social behaviors increased when the children played with unpopular toys more than with popular toys. This latter tendency, however, did not apply to girls with low sociability.