Purpose To investigate whether experimental autoimmune uveitis can be induced equally in different rats by urea soluble fraction of bovine melanin-associated antigen(USF-BMAA),and,if so,difference among them. Methods Lewis rats,F344 rats,Wistar rats were immunized with USF-BMAA emulsified with complete Freud is adijuvant and Bordelella pertussis to induce experimental autoimmune uveitis.The animal models were investigated clinically and histopathologically and compared with each other. Rusults Experimental autoimmune uveitis could be induced in Lewis rats,F344 rats and Wistar rats with US-BMAA.Clinical and histopathalogical examination showed that bilateral ocular inflammation developed after immunization 9-13 days.Although inflammation was mainly located in anterior uvea,a mild focal choroiditis was noted in those with severe anterior inflammation.No inflammation was observed in the retina and pineal gland.Experimental autoimmune uveieis induced with USF-BMAA was similar to experimental autoimmune anterior uveitis incited with BMAA presented by other authors.Inflammation induced with USF-BMAA in F344 rats and in Lewis rats was quite similar in the severity and course of the model.But the inflammation was less in Wistar rats compared with that in Lewis rats and F344 rats. Conclusion Experimental autoimmune anterior uveitis was successfully induced with USF-BMAA in Lewis rats,F344 rats and Wistar rats.The difference with regard to the severity among these aminals were propably attributed to their genetic bankground. (Chin J Ocul Fundus Dis,1998,14:149-152)