Objective To explore renin expression in cytomegalovirus(CMV) infected juxtaglomerular cells(JG) and its biological significance. Methods JG model cell line As4.1 cells derived from kidney tissue were respectively incubated with murine CMV at multiplicities of infection(MOI) of 10, 0.1 and 0 for 5 d, and the control was mock infection with the same amount of ultraviolet inactive CMV as MOI 10, then the cells were harvested. CMV immediate early gene(IE1) mRNA in the cells was tested by RT-PCR. The renin positive cells and the renin fluorescence granules in the cells were examined by immunofluorescence stain. Whether or not re-nin antigen and CMV antigen were showed in the same cells by FITC and TRITC immunofluorescence. The renin gene expression in the cells was individually detected by real-time RT-PCR and Western blot. Results The cells infected by CMV showed typical cytopathic effect(CPE) and viral plaques in the cell monolayer. CMV IE1 mRNA was found in the viral infected cells by RT-PCR. The mass or ring granules of renin positive fluorescence appeared in the cytoplasm of the CPE cells. The renin positive cells congregated around the viral plaques. Renin positive granules and CMV positive granules showed in the same cells. Renin expression in the CMV infected cells exhibited in a dependent manner of ratio of infectious virus particles to cells. Conclusion CMV infection of the cells derived from kidney tissue induces renin expression related to a new pathogenesis of cardiovascular diseases.