Phytases (myo-inositol hexakisphosphate phosphohydrolase, EC 184.108.40.206) catalyze the release of phosphate from phytate. Several cereal grains, legumes and oilseeds store phoshorus as phytate. Phytases can be produced from plants, animals and microorganisms. Microbial sources, however, are most promising for commercial exploitations and biotechnological applications. The enzyme has been widely used in animal feeding to improve phosphorus nutrition and to reduce phosphorus pollution of animal waste. Phytases have been also used in food industry, preparation of myo-inositol phosphates, paper industry and as a soil amendment. Biotechnology are using for developing new effective phytases with improved properties.