Abstract: Objective To detect the ratio of CD3+, CD4+, CD8+ T lymphocytes and HCMV-IgG and IgM antibodies in peripheral blood of urothelial carcinoma patients in perioperative period and to evaluate the impact of HCMV infection on immune functions. Methods Thirty-three peripheral blood samples were collected from urothelial carcinoma patients with pathological diagnosis. Flow cytometry was performed to detect the ratio of CD3+, CD4+ and CD8+ T lymphocytes subsets. ELISA was conducted to detect HCMVIgG and IgM antibodies. Patients were divided into positive group and negative group based on HCMVIgM results. T lymphocyte difference was also compared. Results HCMV-IgG antibodies of 31 patients were positively expressed, HCMV-IgM antibodies of 7 patients were positively expressed, and HCMV-IgM antibodies of 26 patients were negatively expressed respectively. CD3+, CD4+ and CD8+ T lymphocytes subsets were statistically different between HCMV-IgM positive and negative groups(P<0.01). The percentage of CD4+ T lymphocytes and CD4+/CD8+ ratio of positive group were obviously less than those of negative group. CD4+/CD8+ ratio showed that the immune function of 85% (6/7) positive group was poor, while there was only 11.5% (3/23) in negative group. There was a statistical difference between two groups (P<0.01). Conclusion Detecting HCMV-IgM preoperatively may predict the cellular immune functions of patients with urothelial carcinoma, contributing to perform adjuvant therapy after operation