Gamm globulin can reduce febrile course (8.3 ± 2.07 vs 13.41 ± 3.32, P: 0.001), shorten in-hospital period (7.1 ± 1.37 vs 12.8 ± 5.13; p: 0.005), decrease inflammatory reactions by rapidly reducing of VS and CRP, decrease percentage (20% vs 58.8%) and degree of coronary artery aneurysm (3.3% vs 60%) without any significant side effects.