Abstract:The diuretic effect of extract of Luobuma (Apocynum venetum) leaves was tested by two methods (metabolic cage and ureter collecting test) in three species of animals (rat, rabbit and dog). The diuretic effect occurred with increasing the amounts of both sodium and kalium, but no change in concentration of both ions in urine. In the meantime the kalium level of blood was no changed significantly. The mechanisms of the diuretic effect of Luobuma were discussed.