In this study, we propose that infant social cognition may 'bootstrap' the successive development of domain-general cognition in line with the cultural intelligence hypothesis. Using a longitudinal design, 6-month-old infants (N = 118) were assessed on two basic social cognitive tasks targeting the abilities to share attention with others and understanding other peoples' actions. At 10 months, we measured the quality of the child's social learning environment, indexed by parent's abilities to provide scaffolding behaviors during a problem-solving task. Eight months later, the children were followed up with a cognitive test-battery, including tasks of inhibitory control and working memory. Our results showed that better infant social action understanding interacted with better parental scaffolding skills in predicting simple inhibitory control in toddlerhood. This suggests that infants' who are better at understanding other's actions are also better equipped to make the most of existing social learning opportunities, which in turn may benefit future non-social cognitive outcomes.