The effect of atractylis on the renal function of the dog was investigated in this study. Alcohol extract of atractylis, when given intravenously in dose 15mg/kg, elicited antidiuresis rather than diuresis. Also, free water clearance $(C_{H_2O})$ decreased in proportion. No alterations of the renal clearances of creatinine and PAH were detected in the range of doses which are effective in inhibiting diuresis. The effects were obtained with smaller doses when the atractylis was given through the intracarotid artery route rather than intravenously. When infused directly into a renal artery, atratylis exhibited identical action on both kidneys, indicating that the renotropic action is mediated by some endogenous humoral agents. It is therefore suggested that atractylis is capable of releasing ADH from the neurohypophysis.