Abstract: A strain of Cryptosporidium derived from quail was identified as C.meleagridis in previous experiment.The pathogenicity of the Cryptosporidium strain to ostriches,chickens,ducks and mice were studied,these experimental animals were divided into infective group, immunosupressive group and control group respectively. There were only diarrhea in quail, chicken, mice, ducks which infected with C.meleagridis, but no clinical signs in ostriches.There were multiple peaks in those immunosuppressive experimental animals. The experiments were carried out on pathology of some organs in young chickens and mice that infected with Cryptosporidium meleagridis from quail, we found that Cryptosporidium derived from quail mainly parasitized in duodenum of mice and ileum of chicken which challenged with it, the intestinal villi of these experimental animals became atrophied and desquamated.A few parasites were found in ileum of duck.The results suggest that the duck is a new host of C.meleagridis from quail, and the ostrich can′t be infected by this C.meleagridis. Parasitic site of C. meleagridis from quail in quail, chicken,duck were different from that of mice.