Abstract: OBJECTIVE To explore the influence of Chlamydia pneumoniae infections on cardiovascular system of patients with uremia so as to provide guidance for clinical diagnosis and treatment. METHODS A total of 106 patients with uremia who were treated in the hospital from Jan 2015 to Dec 2016 were recruited as the study objects, of whom 53 did not have C.pneumoniae infection were assigned as the control group, and the patients who had C.pneumoniae infection were set as the infection group.The proportion of the type 17 helper T (TH17) cells and regulatory T cells (Treg) was compared between the two groups of patients with the use of flow cytometry, the levels of cytokines IL-17, IL-6 and IL-10 were compared between the two groups of patients, indexes such as stroke volume (SV), output per minute (CO), stroke index (SI), ejection fraction (EF) and total peripheral resistance (TPR) were compared between the two groups of patients by means of cardiovascular analyzer. RESULTS The proportion of the TH17 cells and Treg cells was 11.33±5.07 in the infection group, significantly higher than 3.99±0.58 in the control group(P＜0.05).The levels of cytokines IL-17, IL-6 and IL-10 were respectively (61.07±11.72)pg/ml, (52.61±10.19)pg/ml and (7.02±3.18)pg/ml in the infection group and were respectively (15.33±5.71)pg/ml, (14.29±3.67)pg/ml and (27.69±5.43)pg/ml in the control group; the levels of cytokines IL-17 and IL-6 of the infection group were significantly higher than those of the control group, the IL-10 level of the infection group was significantly lower than that of the control group(all P＜0.05).The cardiac function of the infection group was worse than that of the control group, the SV, CO, SI and EF of the infection group were significantly less than those of the control group, the TPR of the infection group was significantly greater than that of the control group(all P＜0.05). CONCLUSION The proportion of the TH17 cells and Treg cells is out of balance in the uremia patients when they have C.pneumoniae infection, the levels of proinflammatory factors IL-17 and IL-6 are elevated, the anti-inflammatory cytokine IL-10 level is reduced, which therefore leads to the cardiovascular dysfunction and has adverse effect on the life of the patients.