Background. Given the increasing prevalence of primary tooth caries in Iran and the importance of providing evidence- and theory-based family-centered prevention programs, the present study is aimed at determining the family-centered social cognitive factors preventing deciduous tooth caries among children using the intervention mapping protocol. Methods. This cross-sectional study was performed on 240 Iranian mothers in Ilam who were randomly selected to participate in the study. The data were collected using a self-designed questionnaire including items on demographic information and social cognitive constructs (knowledge, attitude, perceived severity, perceived benefits, perceived barriers, practice guidance, perceived self-efficacy, behavior intention, subjective norms, and social norms). The questionnaire was completed by mothers, and the data were analyzed by performing one-way analysis of variance and linear regression. Results. The results obtained from linear regression analysis showed that perceived self-efficacy (B = 0.295 , p < 0.001), perceived barriers (B = 0.084 , p < 0.028), practice guidance (B = 0.774 , p < 0.001), and social norms (B = 0.137 , p < 0.020) accounted for 71% of the behavioral intention variance and were the most important predictors for preventing primary tooth caries among children. Conclusion. The findings suggest that perceived self-efficacy, perceived barriers, practice guidance, and social norms are essential for developing family-centered programs to prevent primary tooth caries in children.