The purpose of this study is to examine the long and short-term effects of aggressive behaviour with peers, asocial behaviours with peers, and excluded by peers levels of preschool children on the social-emotional variables (making contact-social performance and self-control-thoughtfulness). In this study, where five-yearold children were included, the pre-school education teachers completed the Child Behaviour Scale (aggressive with peers, asocial behaviours with peers and excluded by peers subscales) and Social-Emotional Well-Being and Resilience Scale (making contact-social performance and self-control-thoughtfulness subscales). According to the findings of the study, the problems in peer relationships decreased in the second measurements compared to the first measurements, while the social-emotional variables increased in the second measurements compared to the first measurements. In the study, the three problems faced in peer relationships predicted at least one of the social-emotional well-being variables both in the short-term and the long-term. This result may be interpreted as the fact that peer relationships have strong effects on social and emotional development.