Current study was to evaluate the prevalence of guideline recommended medications adherence in myocardial infarction (MI) patients postpercutaneous coronary intervention (PCI) and the association of medication nonadherence and major adverse cardiovascular events (MACEs).MI patients who underwent PCI in the last 12 months were enrolled. Demographic and clinical characteristics were collected and guideline recommended medications were evaluated. Patients were divided into with and without MACEs groups.Compared to patients without MACEs, those with MACEs were older (54.8 ± 16.4 vs 51.1 ± 15.2 years), more likely to be smoker (40.2% vs 31.9%), have higher body mass index (BMI; 25.0 ± 6.1 vs 23.8 ± 5.7 kg/m), diabetes (47.5% vs 37.8%), ischemic stroke (34.4% vs 25.6%), and estimated lower glomerular filtration rate (85.4 ± 9.6 vs 92.6 ± 10.7 mL/minute/1.73 m). Patients with MACEs were also more likely to present with ST-elevation MI (STEMI; 54.1% vs 48.4%) and to undergo urgent PCI (62.3% vs 56.3%). Furthermore, patients with MACEs were less likely to adhere to dual antiplatelet therapy (77.9% vs 85.9%), renin-angiotensin system inhibitor (62.3% vs 69.7%), and beta-blocker (69.7% vs 72.8%) treatment. In unadjusted model, medication nonadherence was associated with 2-fold higher odds of MACEs. After adjustment for demographics, risk factors, comorbidities, and peri-PCI characteristics, medications nonadherence remained independently associated with MACEs, with odds ratio of 1.40 (95% confidence interval: 1.29-1.87).Medications adherence rate among MI patients post-PCI is suboptimal in China, which is independently associated with MACEs.