Abstract: Objective To establish a food allergy animal model in young mice with OVA and observe the intervention effect of CPG oligodeoxynucleotides (CPG-ODN) on food allergy in the animal model. Methods Forty female BALB/c mice (2-3 week) were used to establish the food allergy animal model. They were randomly divided into five groups:Control group, OVA induced food allergy groups (20 μg group; 50 μg group; 100 μg group) and CPG-ODN intervention group (50μg OVA+CPG-ODN) (n=8). The allergic symptoms were observed and scored. Blood samples were collected from each mouse. Serum Th1/Th2 cytokine, OVA-IgE and mMCP-1 levels were determined. Jejunal tissue was taken for histopathological examination. Results Some allergic symptoms appeared, the pathological characteristics of I type allergic reaction were shown in jejunal tissue, Th2 cells and levels of serum OVA-IgE and mMCP-1 were increased in all mice except the control group. Mice in 20μg or 50μg of OVA induced food allergy group also showed a decrease in Th1 cells. All these allergic reactions were most obvious in mice with food allergy induced by 50μg of OVA. However, these changes were significantly reduced in mice of intervention group, while the levels of Th1 increased. Conclusion The best sensitization effect is shown in food allergy animal model of young mice with 50μg of OVA injection. CPGODN can inhibit the allergic reactions in these mice through improving the levels of imbalanced Th1/Th2. The mMCP-1 plays an important role in immune pathogenesis and it may be a detecting indicator of allergic disease.