Effects of saikosaponin d extracted from Bupleuri Radix on the antigranulomatous action of glucocorticoid were investigated in rats by the cotton pellet method. Saikosaponin d (0.1 mg/kg/day x 4 days) and dexamethasone (0.1 mg/kg/day x 4 days) reduced the weight of cotton-induced granuloma to 89.58% and 88.54% of the control, respectively. These antigranulomatous actions failed to show a significant difference from the control. However, the combined administration of saikosaponin d and dexamethasone produced a significant antigranulomatous action, namely, the decrease in the weight of granuloma to 62.5% of the control. While the combination of saikosaponin d and dexamethasone showed an inhibitory trend against the increase in serum triglyceride as induced by dexamethasone, the cholesterol level was elevated by the combination. The body weight was significantly reduced by the combined administration as compared with the group treated with dexamethasone alone, but no apparent difference existed in the adrenal and thymus weights between them.