The ultrastructural changes and morphogenesis in the intestinal epithelial cells of infected BALB/c suckling mice with murine rotavirus were observed. The epithelial cells showing some huge vesicles of endoplasmic reticulum were filled with clumps of MRV and masses of lipid material. The MRV finished the process of morphogenesis in the viroplasma and inclusion, and some mic-rotubule-like structures related to replication of MRV were also described in the report.