The scope of this study was to discriminate factors, which could improve students' social relationships in kindergarten classrooms. In this research, 147 volunteer children participated, 67 female students and 80 male students. Every student was between 4.5 and 5.5 years old and they were all attending urban public kindergarten located in central Greece. This study focuses on factors associated with the students' social ability to develop healthy relationships in kindergarten classrooms. Direct observations of children's friendship skills and social play participation, questionnaires for children's social behaviour filled out by teachers and sociometric data were gathered for data analysis. The collected data ware analysed through correlational and Multiple Linear Regression Analysis. Results indicate that social behaviour, social play and social skills for developing friendships have an impact on children's relationships. Higher scores in 'cooperation', 'social collaborative game' and 'social skills for sustaining friends' are positively associated with peer acceptance and friendship. All of the above are highly significant variables for the prediction of healthy relationships in early childhood. All models showed effects, which are meaningful in socio-pedagogical applications.