Hygroryza aristata is the significantly most important traditional medicinal plant practitioners all over the country since long years. Traditionally it is used as diuretic, emollient, galactagogue, strangury, diarrhea, otopathy, fatigue, general debility, Seeds are cooling and astringent to urinary tract; useful in biliousness. By using this plant only two investigations were done like: anti-inflammatory and antioxidant activities. The purpose of the study was to determine the anti-diarrheal, anthelmintic and antimicrobial activity of Hygroryza aristata leaves extract. Phytochemical screening of the methanolic extract of Hygroriza aristata leaves indicates the presence of alkaloids, carbohydrates, flavonoid, glycoside and steroid. The antimicrobial activity was investigated by the disk diffusion method using microorganisms. The antibiotic discs of Ciprofloxacin were used as reference standard. The methanolic extract of the leaf of Hygroriza aristata (250μg/disc and 500 μg/disc) showed a promising anti-microbial activity against Bacillus subtilis and Vibrio metschnikovii. In anthelmintic assay the plant extract exhibited that animal were paralyzed and finally dead within long time as compared with the standard drug Albendazole, which assuming that the plant extraxt has a promising anthelmintic effect with a long duration of action. In the investigation of anti-diarrheal activity comparing with the standard drug Loperamide we found that the number of faeces was markedly reduced by both the standard drug Loperamide (72.73%) as well as the plant extract, with the concentration of 300mg/kg (36.37%) and 600mg/kg (54.55%) respectively. Percentage of faecal output was also reduced with the increase of doses of the extract. Thus, we can assume that, Hygroriza aristata plant have a promising effect of anti-diarrheal, anti-microbial and anthelmintic effect which showed a ways of inventing new lead compound having such type of pharmacological effects respectively.