Objectives: The present study evaluated associated factors for developing early childhood caries (ECC) and Severe-ECC (S-ECC) in a group of children aged 24-71 months. Potential positive effects of early dental visit on formation of ECC is investigated as well. Study Design: This was a multicenter, cross-sectional study conducted at three governmental and university pediatric dentistry clinics in 408 preschool children who were randomly selected from a total of 4116 children. The questionnaires administered to the mothers by interview and intraoral examination performed by calibrated pediatric dentists. The children were evaluated in three groups according to their caries experience as who had caries free, ECC and S-ECC.