Bullying in schools has been identified as a serious and complex worldwide problem associated with negative short-and long-term effects on children's psychosocial adjustment (Smith 1999; Ttofi and Farrington, Aggressive Behav 34(4):352-368, 2008). Entering kindergarten is a crucial developmental step in many children's lives mainly because it is within this context where they participate, for the first time, as members in a stable peer group and well-organized team activities. Consequently, preschool may be the first context beyond the home environment where children's difficulties in social interactions with peers can be primarily detected and assessed by adults and professionals. This paper reviews recent empirical evidence over the nature and different aspects of bullying among preschool children. Recent findings concerning the development of preschool bullying and its prevalence, family and genetic factors, gender and age differences, participant and peripheral roles, school context, methodological issues, and prevention policies are reviewed while directions for future research are addressed.Bullying in schools has been identified as a serious and complex worldwide problem associated with negative short-and long-term effects on children's psychosocial adjustment (Smith 1999;Ttofi and Farrington 2008). Most of the research undertaken for studying bullying in schools has emphasized on middle childhood and adolescence, while there is scarce empirical evidence concerning the manifestation and development of the problem in early childhood years (