Abstract: OBJECTIVE To explore the effect of Xuebijing injection on treatment of postoperative pulmonary infection in acute myocardial infarction (AMI) patients undergoing percutaneous coronary intervention (PCI) and observe its impact on the levels of serum interleukin (IL), tumor necrosis factor (TNF)-α and high-sensitivity C-reactive protein (hs-CRP). METHODS A total of 68 AMI patients who received PCI in the hospital were enrolled in the study and randomly divided into the control group with 39 cases and the observation group with 39 cases. All of the patients received emergency PCI after the admission to hospital. The control group was treated with conventional antibiotics for intervention on the third day after the surgery, while the observation group was given additional Xuebijing injection on bas is of treatment of the control group on the third day after the surgery, and both group were treated for 2 consecutive weeks. The time of disappearance of clinical symptoms, white blood cell (WBC ) counts and clinical pulmonary infection score (CPIS) were observed and compared between the two group of patients; the levels of T lymphocyte subsets CD₃⁺CD₄⁺ and CD₃⁺CD₈⁺ of the two groups of patients were determined by using flow cytometry, and the levels of serum IL-6, TNF-α and hs-CRP were detected. RESULTS The time of recovery of body temperature, time of cough and time of disappearance of pulmonary rales were significantly shorter in the observation group than in the control group (P＜0.01). The WBC counts and CPIS of the observation group were significantly lower than those of the control group after the treatment (P＜0.01). The CD₃⁺CD₄⁺ level of the observation group was significantly higher than that of the control group after the treatment, while the CD₃⁺CD₈⁺ level of the observation group was significantly lower than that of the control group (P＜0.01). The levels of serum IL-6, TNF-α and hs-CRP of the observation group were significantly lower than those of the control group (P＜0.01). CONCLUSIONS On basis of the conventional antibiotics, Xuebijing injection may remarkably improve the postoperative pulmonary infection in the AMI patients undergoing PCI, boost the immunity and reduce the inflammatory reactions.