Abstract: Objective To investigate the extraintestinal dissemination of rotavirus (RV) in immunodeficient mice.Methods Immunodeficiency mouse model was established by injection of cyclophosphamide into the abdominal cavities of normal mice, then to which RV was administered either orally or intra-abdominally. The pathological changes in the organs were observed by light microscopy and RV was detected by in situ hybridization and PCR.Results Small intestinal villi, gastric lamina propria and cardiac myocytes exhibited pathological changes in the mice with oral RV administration. Besides these changes, the mice with intra-abdominal RV injection showed changes in the liver and kidneys. The intestinal villi of the mice with oral RV were RV positive by in situ hybridization. Positive results of RV in in situ PCR detection were found in the intestinal villi, intestinal gland cells, epithelial cells of the proximal convoluted tubules and collecting tubes in the kidney of the mice taken RV orally, and in the intestinal villi, kidneys, liver, heart and pancrease of mice with intra-abdominal RV injection.Conclusion Immunodeficiency may be the important factor for inducing and aggravating the infection and extraintestinal dissemination of RV.