PROBLEM TO BE SOLVED: To provide a manufacturing method of ground processed meat products excellent in juicy feeling and texture, preventing effluence of meat juice during heating, with high heating yield and a modifier for ground processed meat products.SOLUTION: The manufacturing method of ground processed meat products includes utilizing a protease derived from Bacillus amyloliquefaciens, having the following characteristics: (a) effect and substrate specificity: a substrate having a peptide bond is hydrolyzed to separate peptide (b) optimal pH: 7.0 (c) stable pH: 5.0 to 7.0 (d) optimal temperature: 50 to 55°C and (e) inhibitor: a metal protease, which is inhibited by EDTA. Trisodium citrate or arginine is further contained as alkali material.COPYRIGHT: (C)2014,JPO&INPIT