The infection of cyprinid herpesvirus Ⅱ (CyHV 2) in cultured gibel carp (Carassius auratus gibelio) is a newly emerged severe disease and has caused huge economic losses. Currently, little information about the pathogenesis of disease is available. In this study, the healthy gibel carp was peritoneally injected with the ultra filtrated homogenate from the inner organs of diseased gibel carp infected by CyHV-2. 3 days later, the periphery blood from the infected gibel carp and the control group were collected for the investigation of blood biochemical indices, including haematocyte number, differential leucocyte count (DLC), phagocytic activity of phagocytes and serum biochemical indices, etc. The results showed, compared with the control group, the total cell number in periphery blood of the artificially infected fish had no apparent change, but the percentages of monocyte and lymphocyte were increased significantly, in which the lymphocyte percentage indicated highly significant difference（P＜0.01）and the monocyte percentage was of significant difference（0.01＜P＜0.05）; The percentages of neutrophilic granulocyt and thrombocyte in the infected group were declined at significant level（0.01＜P＜0.05). Meanwhile, the phagocytic percentage(PP) and phagocytic index (PI) of monocyte in the infected group was significantly higher than that of the control group（P＜0.01）, and the PP and PI of erythrocyte showed significant difference（0.01＜P＜0.05）.The total protein in the serum of infected fish was （34.32±2.52）mmol/L, which was significantly higher than that in the control group（28.00±2.17）mmol/L（0.01＜P＜0.05）; Highly significant increases of alanine aminotransferase(ALT), aspartate aminotransferase(AST) and alkaline phosphatase were found in the infected fish compared to the healthy fish（P＜0.01）.The concentrations of ALT,AST and ALP were （21.50±1.58）U/L,（407.50±4.52）U/L and （51.00±5.27）U/L in the challenged fish, respectively, while in the control group, they were （12.67±1.32）U/L,（346.50±3.07）U/L and （17.50±4.88）U/L. In contrast, the concentrations of triglyceride, total cholesterol and blood glucose in the infected group were declined, but showing no significant difference（P＞0.05）.