<p>Parents are often required to manage their children’s negative emotions. Some of the emotion socialization practices that parents exert in these situations are considered to be non-supportive (e.g., punitive and/or dismissing responses) and have been linked to greater socioemotional difficulties of their children. While previous studies suggest that parental temperamental tendencies may underlie these non-supportive responses, the exploration of such a mechanism remains limited. This study aimed to test the moderation between reactivity and self-regulation at the brain activity level, for explaining non-supportive emotion socialization practices of mothers. Participants included 161 mothers of kindergarten-aged children. The non-supportive parenting practices factor was extracted based on self-reports, and reactivity (i.e., frontal alpha asymmetry) and self-regulation (i.e., NoGo N2 amplitude) were extracted from EEG recordings. The analyses revealed that for mothers with withdrawal reactive tendency, their self-regulation was not related to their use of non-supportive parenting practices, and was generally lower than average. However, for mothers with approach reactive tendency, the more resources of self-regulation they had, the less they reported they used non-supportive parenting practices.</p>