Purpose: To evaluate the prevalence of early childhood caries (ECC) and severe ECC (S-ECC) among Italian preschool children and its predictors regarding children's lifestyle. Materials and Methods: A cross-sectional study was carried out involving 563 preschool children. A questionnaire for children's parents and clinical examinations were conducted by calibrated, blinded examiners. The odds ratios (OR) for ECC or S-ECC and co-presence of risk factors were calculated using univariate and multivariate models. Statistical significance was set at p 0.05 in all analyses. Results: The prevalence of ECC and S-ECC was 14.4% and 5.9%, respectively. According to the multivariate analysis, the predictors for caries were (p 0.05): age (OR = 2.5; 95% CI = 1.36 - 4.52), non-Italian ethnic origin (OR = 4.3; 95% CI = 2.83 - 7.37), consumption of sugary beverages more than once per day (OR = 2.1; 95% CI = 1.21 - 5.26) and having inadequate oral hygiene status (OR = 3.6; 95% CI = 2.01 - 5.83). Conclusions: Dietary habits and dental care are important environmental contributing factors in the development of caries in preschool children. Oral health promotion should include an oral hygiene instruction programme and dietary guidelines focused on daily sugar intake for the preschool children themselves as well as for their parents. Parole chiave: children, early childhood caries, feeding habits, prevention, public health