Caregivers’ beliefs about their ability to parent successfully play an important role in parent and child adjustment. Yet the cognitive processes through which parental self-efficacy beliefs may influence parental well-being have been understudied to date. The first aim of the present study was to evaluate the psychometric properties of the Hungarian version of the Parenting Sense of Competence Scale (PSOC). The second aim was to test a moderated mediational model of parental well-being, drawing on social cognitive theory. In a sample of 407 mothers of non-clinical children aged between 4 and 18 years, confirmatory factor analysis supported a two-factor solution for the PSOC, as suggested by the original authors. The Hungarian version of the PSOC showed good internal consistency and test-retest reliability. Next, we used conditional process modelling to test our hypothesised model in which the relationship between parental self-efficacy and role satisfaction is mediated by cognitive emotion regulation strategies, conditional on the level of parental self-efficacy. This model was partially supported. Self-blame mediated the relationship between parental self-efficacy and parental role satisfaction only when self-efficacy was low, while planning was found to be a significant mediator independent of the level of self-efficacy. Targeting these cognitive factors may improve parent interventions.