To establish an oral Brown Norway(BN)rat model for food allergy. Methods Different doses(0.1,1.0, and 10.0mg/d)of ovalbumin(OVA)were administered to male and female BN rats with different age (4and 8weeks) by gavage for 35days. Specific serum IgE against OVA on the 28^th and 35^th days was analysed by enzyme-linked immunosorbent assay(ELISA). Results Daily gavage of 1.0mg OVA to 4-week female and 8-week female BN rats resulted in significantly higher concentrations of OVA sIgE on day 28and 35compared to the control group(P＜0.05). On day 28, the concentration of OVA sIgE was significantly higher in 8-week male BN rats exposed to 0.1mg OVA/day than the control group(P＜0.05). The concentration of OVA sIgE had no significant difference among all groups of 4-week male BN rats on day 28and 35. Conclusion Different doses of OVA were administered orally to BN rats with different sex and age. Females were more sensitive than males; age did not significantly influence the concentration of OVA sIgE; the better dose was 1.0mg. Therefore, an ideal animal model of food allergenicity can be established by 1.0mg/d OVA gavage to female BN rats for 28～35days.