Precedent studies concerning play and social behavior of preschool children had explored how preschool children change their play which accompanied with others. In the present study, the authors explored how preschool children change their non-social play which did not accompany with others from the view point what play the preschool children do next to the non-social play. As the result from the event sampling method, the number of the case of solitary passive play was slgnificantly larger than that of reticent play. And the number of the change from the solitary passive play to play with others (i.e., other preschool children or caregiver)was larger than that fom the solitary passive play to reticent play. These results suggested that in the case of the play with others were attractive, the preschool children fnish their solitary passive play and start to play with others. Finally, the characteristics of the change of non-social play and the implications of non-social play for social adjustment were discussed.