Abstract: The yak hemoglobin from blood was hydrolyzed in order to produce protein polypeptide with neutral protease. The factors influencing neutral protease to hydrolyze yak hemoglobin and their relationships with hydrolysis degree were explored by single factor experiments and orthogonal design [L16(45)]. And the effect of activated carbon on decolorization was analyzed. The results showed that the optimum hydrolysis conditions were as follows: pH 7.0, temperature 45℃, enzyme activity 4000 U/g substrate, substrate concentration 5%, hydrolysis duration 7 h. The optimum parameters for decolorization were determined to be active carbon consumption of 4%, temperature of 75℃, pH 5.0 and decolorization duration of 60 min.