OBJECTIVE： To explore the effects of Xuesaitong injection on related indexes of patients with acute ST segment elevation myocardial infarction （STEMI） before percutaneous coronary intervention （PCI）. METHODS： 112 STEMI patients underwent PCI were analyzed retrospectively and divided into control group （48 cases） and observation group （64 cases） according to different treatment methods. Control group was given Clopidogrel sulfate tablets 300 mg and Aspirin enteric-coated tablets 300 mg orally before PCI； given conventional treatment according to patients’ condition after surgery. Observation group additionally received intravenous push of Xuesaitong injection 8 mL before surgery， and Xuesaitong injection 8 mL added into Sodium chloride 250 mL intravenously， once a day after surgery， on the basis of control group. Treatment course of 2 groups lasted for 14 d. TIMI level， MPG level， the serum levels of cTnT， CKMB were observed in 2 groups before surgery， 24 h after surgery； serum level of PTX-3， hs-CRP were observed before surgery， one week after surgery； LVEF， LVEDD， serum level of BNP were observed before surgery and one month after surgery； the occurrence of ADR was observed to. RESULTS： Before surgery， there was no statistical significance in TIMI level， MPG level， the serum levels of cTnT， CKMB， PTX-3 and hs-CRP， LVEF， LVEDD， serum level of BNP between 2 groups （P＞0.05）. 24 h after surgery， TIMI level and MPG level of 2 groups were significantly higher than before， and the observation group was significantly higher than the control group； the serum levels of cTnT and CKMB in 2 groups were significantly lower than before， and the observation group was significantly lower than the control group， with statistical significance （P＜0.05）. One week after surgery， the serum levels of PTX-3 and hs-CRP in 2 groups were significantly lower than before surgery， and the observation group was significantly lower than the control group， with statistical significance （P＜0.05）. One month after surgery， the level of LVEF in 2 groups were significantly higher than before surgery， and the observation group was significantly higher than the control group； LVEDD and serum level of BNP in 2 groups were significantly lower than before surgery， and the observation group was significantly lower than the control group， with statistical significance （P＜0.05）. There was no statistical significance in the incidence of ADR between 2 groups （P＞0.05）. CONCLUSIONS： Based on conventional treatment， Xuesaitong injection can effectively improve myocardial blood supply before PCI， decrease the level of inflammatory factor， relieve myocardial injury， improve cardiac function without increasing the incidence of ADR.