Drawing on social information processing theory, through the analysis of three-wave data (including 514 valid samples from front-line knowledge workers in knowledge-based enterprises), this study investigates a dual process model, which encompasses both psychological safety and affective commitment mechanisms, to reveal how platform leadership inhibits employees’ knowledge hiding. It also examines the moderating role of person-supervisor fit. The results indicate that, platform leadership significantly enhances knowledge employees’ psychological safety and affective commitment, thereby effectively reducing their engagement in knowledge hiding behavior. In addition, person-supervisor fit positively moderates the indirect effect of platform leadership on knowledge hiding through psychological safety and affective commitment, that is, when the degree of fit between superiors and subordinates is high, the above-mentioned indirect effects are stronger, and vice versa.