Based on the comparison and comprehensive utilization of amino acid fermentation wastewater treatment methods，this paper summarized the current commonly used treatment process of the amino acid fermentation wastewater: fermented waste liquid → extraction of bacterial protein → multiple effect concentration→spray granulation→organic inorganic compound fertilizer． A lot of researches on the secondary pollution of gas in the process of spray granulation in Fufeng group has been carried out． After gas treatment， the concentration of dust was reduced from 180 mg /m3 to 100 mg /m3， and the concentration of odor emission reduced from 20 ( dimensionless) to 15 ( dimensionless) ．