Although affect has been considered to be an important antecedent to employee creativity, the extant findings are mixed, and the literature is inconsistent and unsystematic, and fails to explore the organizational determinants of the employee affect. Based on the affective events theory, this article investigates the relationship among leader-member exchange (LMX), positive / negative affect and employee creativity, and the moderating effect of the perceived organizational support for creativity. With a sample of 442 supervisor-subordinate dyads, the research finds that positive and negative affect significantly mediate the relationship between LMX and employee creativity, perceived organizational support for creativity (POSC) positively moderates the relationship between positive affect and creativity, whereas its moderating effect on the relationship between negative affect and creativity is non-significant. POSC also determines the extent to which positive and negative affect account for the effect of LMX on employee creativity.