The objective of this experiment was to investigate the effect of dietary supplementation of copper-soy proteinate (Cu-SP) and herbal mixture (HBM) on growth performance, blood parameter, and immune response in laying hens. A total 800 Hy-Line Brown laying hens (60 weeks old) were randomly allotted to 1 of 4 dietary treatments : (1) Control : control diet, (2) Cu-SP : control diet + 100 mg/kg Cu-soy proteinate, (3) HBM : control diet + 0.15% herbal mixture, and (4) Cu-SP + HBM : control diet + 100 mg/kg Cu-soy proteinate + 0.15% herbal mixture. Each treatment was replicated 5 times with forty birds units were arranged according to randomized block design. Feeding trial lasted 5 weeks under 16L : 8D lighting regimen. The diet and water were available ad libitum. Result indicated that during feeding trial of the experiment, hen-day egg production was significantly (P<0.05) higher in Cu-SP and HBM treated groups than control. However, feed intake, feed conversion ratio, egg weight, broken and shell less egg production were not significantly influenced by treatments. Eggshell strength was significantly (P<0.05) higher in Cu-SP than control. Eggshell thickness, eggshell color, egg yolk color, Haugh unit were not significantly influenced by treatments. The level of WBC and stress index (heterophil : lymphocyte) were higher in supplemented groups than the control. The concentration of plasma IgG was higher in supplemented groups than the control. The result of this experiment showed that dietary copper-soy proteinate or herbal mixture tended to improve egg production and affect positively on immune response of laying hens.(Key words : Cu-soy proteinate, Herbal mixture, laying hens, productive laying performance, immune response) † To whom correspondence should be addressed : banght80@korea.kr 서 론 구리(Cu)는 cytochrome oxidase, lysyl oxidase, ceruloplasmin, superoxide dismutase와 같은 수많은 효소들의 작용에 도움을 주는 필수 광물질이다 (Klasing, 1998). 산란계에서의 Cu 요구량은 정확히 제시되어 있지 않지만 (NRC, 1994), 약 리적 수준(sub-therapeutic)으로 100∼300 mg/kg의 사료 내 황산동 형태로 첨가 시 성장 촉진 효과가 있다고 보고되었다 (Klasing, 1988