Social competence is a crucial developmental task for preschool children that involves higher neurocognitive processes. Research has revealed the significance of parenting stress and parenting behavior influencing the development of social competence during the preschool period. Nonetheless, the mechanism of relationship between parenting stress, parenting behavior, and child's social competence development has not been well explored. Furthermore, limited studies have investigated the mediating role of parenting practice in the relationship between parenting stress and child's social competence. This research aims to explore the role of parental autonomy support as one of parenting behavior as a mediator in the relationship of parenting stress and 4-6 years old child's social competence during COVID-19. Children aged 4-6 years old (N = 56) and their parents participated in the current study. Children's social competence and parents' level of parenting stress were measured through two different parent-report questionnaires, and parental autonomy support was observed during the dyadic interaction. Data collection and observations are conducted online. Results indicate that parent autonomy support fully mediates the relationship of parenting stress and preschool children's social competence. This research extends previous studies about the indirect effect of parenting stress on preschool children's social competence mediated by parenting behavior in a pandemic condition. © 2023 American Institute of Physics Inc.. All rights reserved.