Many young children spent a major part of their day in formal preschool type-setting. The purpose of this study was to determine if gross motor development of preschool children is affected by preschool-type setting (public vs private). The sample consisted of 300 preschool children of both sexes (136 boys and 164 girls) aged 4-6 years who were enrolled at the two different types of preschool centers of Northern Greece. Half of the children (n=150) attended private preschool centers which had plenty of open space for playing, gymnasia, courts and playgrounds and included daily exercise physical activity programs. The rest (n=150) participated in formal public preschool centers that had limited spaces for sports and free play and did not include any physical education lessons into their schedule. The gross motor development of the children was assessed using the locomotor scale of the Griffiths test No II (Griffiths, 1984). The analysis of variance showed that children who attended the private preschool typesetting displayed higher quotients and could execute at a younger age every item of the locomotor scale. The results of the present study suggest that gross motor development of preschool aged children is affected by the stimulation level of school environment.