PurposeDrawing on social exchange theory, this study investigates the relationship between supervisors’ psychological closeness and employees’ taking charge at work. Furthermore, it examines the mediating role of trust in the supervisor and the moderating effect of employee power distance orientation.Design/methodology/approachThe study employs structural equation modeling in Mplus (version 8.6) to analyze multi-source data collected from a diverse sample of employees and supervisors, testing the proposed relationships.FindingsThe findings indicate that supervisors’ psychological closeness positively impacts employees’ taking charge at work. Trust in the supervisor mediates this relationship, providing insights into the underlying psychological mechanisms. Additionally, employee power distance orientation moderates the link between psychological closeness and trust in the supervisor, thereby influencing the indirect effect of psychological closeness on taking-charge behaviors through trust.Originality/valueThis study offers a deeper understanding of how relational and cultural factors, including supervisor closeness and power distance orientation, jointly influence proactive work behaviors. It contributes to the literature by highlighting the relationship between psychological and cultural factors in shaping employees’ work behaviors.