Abstract: The decoctions of four herb drugs, used for the treatment of edema in Chinese medicine were studied for their diuretic effect in saline-loaded normal rats. It was found hat Cangzhu (Rhizoma Atractylodis) produced a marked increase in the Excretion of sodium, chloride and potassium ions, but no significant change in the urine output, and that the saluretic-diuretic action of Bianxu (Herba Polygoni Aricularis) was mainly due to its potassium ion content, while Yuanhua (Flos Genkwa) produced both diuresis and diarrhea. Cheqianzi (Semen Plantaginis) was found to have no obvious diuretic effect.