The topic of this diploma thesis is a play as a form of socialization among preschool children. Throughout this paper two fundamental terms have been presented: playing and social development of a child. That is the reason why this paper begins with the chapter concerning the play, which is considered to be a childhood phenomenon of an individual. Playing is the easiest and the most natural means of learning through which children develop cognitive, physical, emotional and social competences. However, although play has a positive impact on all developmental areas, the emphasis is put on social development which is best monitored through playing, which is an excellent way to observe the linkage between these two terms. The aim of the thesis is to examine the way that play influences social development of preschool children from an educator's perspective. In that respect, the research in the private kindergarten “Kockica” and the public kindergarten “Radost“ was conducted for the purpose of this diploma thesis. For this research the method of interview was used and the results show that play has got a positive influence on social development of a child. Namely, a child who adapts to kindergarten surrounding very fast is a good indicator of successful socialization, which is supported by certain child's characteristics: openness and readiness for cooperation, spontaneous and independent engagement into play with other children, good communication with an educator and other children, giving of opinion spontaneously and straightforwardly, participation in new activities, etc.