Phytases are enzymes capable of hydrolyzing phytic acid to myo-inositol derivates and inorganic phosphate - the essential nutrient for animals. Phytate-degrading enzymes have been studied intensively in recent years because of the great interest in such enzymes for reducing phytate content in animal feed and food for human consumption. The supplementation of animal feed with phytases reduces the cost of diets by removing or reducing the need for supplemental inorganic phosphate and increases the bioavailability of phosphorous in monogastric animals. In this study, soils collected from the animal farm and ground soil at Vietnam National University of Agriculture, Gia Lam, Ha Noii used as a source material for isolation of phytase producing bacteria. Phytase screening medium (PSM) was used for isolation. On PSM medium, eight colonies showed clear zones of hydrolysis around them which were replated and hydrolysis efficiency calculated. Among these, Pg isolated from animal farm was found to produce significantly high phytase activity than other isolates. To evaluate the effect of some culture conditions of Pg isolate at temperature range from 30°C to 60°C and at pH range from 3 to 8, at shaken condition at 200 rpm after 60h incubation. The result showed that at pH=4 and 50°C, Pg isolate showed maximum phytase production. The optimum temperature and pH for the activity of phytase of Pg isolate was 50°C and pH=4 respectively (activity reached 94.76 U/ml). To combine morphological and biochemical characters and the result of fatty acid sequence analysis, Pg isolate similar to Bacillus lentimorbus species with similar index is 0.856.