This study investigated the effect of partial fish meal protein replaced by hydrolyzed fish protein concentrate [HFPC] on the growth performance of orange-spotted grouperl. Epinephelus coioides (1.77 g initial weight) were fed five isonitrogenous [45%] and isolipidic [11%] diets containing different levels of HFPC to replace 0, 5, 10, 15 and 20% [0FS, 5FS, 10FS, 15FS and 20FS] of fish meal protein, respectively. Each diet was fed to triplicate groups of fish three times a day until satiation for six weeks. The weight gain percentages of fish fed diets containing HFPC to replace 5, 10, and 20% fish meal protein were significantly [p<0.05] higher than those of fish fed the control diet. The crude protein, crude lipid and ash contents of muscle of fish fed diets containing HFPC were lower than those of fish fed the control diet. The results indicated that diets included HFPC can improve growth performance of fish, and up to 20% fish meal protein can be replaced by HFPC in the diets for orange-spotted grouper Epinephelus coioides.