Background: Previous studies showed that the door-to-balloon (DTB) time was significantly related to the prognosis of patients with ST-segment elevation myocardial infarction (STEMI). In this study, we were committed to evaluating the effect of an optimized clinical pathway on improving emergency treatment for STEMI patients. Method: A total of 315 STEMI patients from January 2018 to December 2019 were enrolled in this study. The clinical characteristics, results of auxiliary examinations and relevant indicators were extracted from the medical records. Result: After optimizing the clinical pathway, the average DTB time in our hospital was 87.57 minutes, which was shortened by 17.71 minutes compared with the control (P = 3.0×10-6). In the optimized group, the time spent in the emergency room was 12.54 minutes less than that in the control group (P = 0.018). In the various workflows of the emergency room, the troponin time and ECG time in the optimized group were reduced by 6.44 minutes and 5.92 minutes, respectively (troponin time: P = 5.0×10-6, ECG time: P = 4.0×10-6). The consultation time was also reduced by 3.91 minutes in the optimized group (P = 0.043). In addition, the hospitalization time for STEMI patients was 9.73 days, which was reduced by 1.15 days after optimization (P = 0.036). Furthermore, the in-hospital mortality rate was decreased from 5.88% to 2.79% (P = 0.172). Conclusion: The optimized clinical pathway could directly reduce the DTB time and improve the prognosis of STEMI patients.