Zea mays Linne belonging to Graminae family has been ordinarily made use of foods and fodder. Maydis Stigma, the stigma of maize, has been discarded without any special application with the exception of being applied as diuretic in the sphere of Chinese medicine, moreover, the pharmacological research toward Maydis Stigma as a medical herb has not been regretfully undertaken at all. The authors hereby paid attention to this point of view and made experiment to find out whether the water extract of Maydis Stigma might possess some pharmacological effect on the motility of the isolated rabbit uterus. The experiment was performed making the use of several agents related to the uterine motility such as acetylcholine, pilocarpine, epinephrine, atropine, barium chloride, quinine sulfate and oxytocin. The motility of the isolated rabbit uterus in Tyrode solution was recorded with the electric kymograph according to Magnus method. The results of the experiment are as follows. 1. The motility of the isolated pregnant and nonpregnant rabbit uterus represents the tendency of gradual contractility in proportion to the concentration of ZW 10^-4, 5 X 10^-4 and 10^-3. 2. The uterine contractile effect of ZW 10^-3 probably seems to antagonize the effect of epinephrine 10^-6. 3. ZW 10^-3 does not seem to have the significance with barium chloride, quinine sulfate and oxytocin respectively.