In order to investigate the antibody level produced in stray dogs by rabies virus CAV2-ΔE3-CGS oral vaccine，and to explore the rule for producing antibody，12 stray dogs in Shanghai were selected for oral vaccine immunization test and to determine the immune antibody by indirect ELISA according to the immunization procedure. The result showed that the qualified rate of antibody produced by CAV2-ΔE3-CGS oral vaccine was 60%，the average antibody levels after primary and secondary immunization reached 0.23 and 0.81 IU/ml，respectively；the average antibody level of oral vaccine tended to increase in general，specifically，the level of protection could not be reached after primary immunization，but reached rapidly after secondary one，and were up to the required level（0.50 IU/mL）in 60% dogs. In conclusion，the antibody against rabies virus could be produced in stray dogs by CAV2-ΔE3-CGS oral vaccine，and the antibody level of 60% dogs could meet the international standard after secondary immunization，and thus provided protection. The immunity of CAV2-ΔE3-CGS oral vaccine was studied in the paper，which provided data support for future development of immunization program and procedure against rabies in stray dogs.