Objective: The aim of the study was to compare emotion regulation among the authoritative, authoritarian and permissive parenting styles of mothers with preschool children. 
Methods: The statistic community of this study was all the mothers in Tehran who had preschool children aged between 4 and 6 years. By convenient sampling, 8 kindergartens were selected, and the questionnaires were completed by mothers. The sample consisted of 270 mothers with preschool children. The participants completed the questionnaires, and the data were analyzed with MANOVA.
Results: Significant difference between the groups in terms of emotion regulation was observed. The authoritative mothers had the highest score in emotion regulation.
Conclusion: Our results indicated that emotion regulation played the main role in different parenting styles.