Abstract: Whey is a by-product in the process of cheese production which contains major whey proteins, lactose and some other water-soluble ingredients in milk.For many small cheese enterprises that can't take advantage of whey, wastewater is the only way to treat.Biotechnology is one of most effective conversion technology for waste, played a key role in the process of biomass conversion.The article summarized the progress of biological treatment of whey in order to provide reference for domestic dairy industry.The main biological technologies include fermentation to methane, ethanol, hydrogen, lactic acid and enzymolysis of lactose.