This paper aimed to review the interferential effect of prolonged dual anti-platelet therapy after Percutaneous Coronary Intervention (PCI), and the influence on reducing the myocardial infarction rate. A computer search was carried out in the relevant libraries and databases, regarding all the short-term (≤ 6 months) and long-term (> 6 months) dual anti-platelet therapies, and the curative and observational studies on the effects and safety of interventional therapy. RevMan5.1 software was used to meta-analyze the standard research. A total of 8 papers were finally selected. In the randomized controlled research, meta-analysis showed that the myocardial infarction rate of a long-term dual antiplatelet treatment group was lower than the short-term treatment group [OR=0.74, 95% CI (0.56, 0.98), P < 0.0001]. The meta-analysis of observational research showed that the myocardial infarction rate of the long-term treatment group was lower than the short-term treatment group [OR=0.7, 95% CI (0.45, 1.08), P=0.11]; the incidence rate of late stent thrombosis in the long-term treatment group was lower than in the short-term treatment group [OR=0.40, 95% CI (0.15, 1.07), P=0.07]. It can be concluded that in the long-term group (>6 months) dual anti-platelet therapy after PCI can reduce the incidence rate of myocardial infarction or death. In addition, long-term treatment can reduce the occurrence tendency of late stent thrombosis. Furthermore, in the long-term treatment group, serious bleeding events did not increase.