Objective There are still a high proportion of patients with ST-segment elevation myocardial infarction (STEMI) missing out early reperfusion even in the primary percutaneous coronary intervention (PCI) era. Most of them are stable latecomers, but the optimal time to undergo delayed PCI for stable ones remains controversial. Methods We investigated all STEMI patients who underwent delayed PCI (2-28 days after STEMI) during 2007-2010 in Beijing and excluded patients with hemodynamic instability. The primary outcome was major adverse cardiovascular events (MACEs). Results This study finally enrolled 5,417 STEMI patients and assigned them into three groups according to individual delayed time (Early group, 55.9%; Medium group, 35.4%; Late group, 8.7%). During 1-year follow-up, MACEs occurred in 319 patients. The incidence of MACEs were respectively 7.1%, 5.6% and 6.7% among three groups. The Medium group had less recurrent myocardial infarction plus cardiac death (hazard ratio, 0.525; 95% confidence interval, 0.294-0.938, P = 0.030) than Late group and less repeat revascularization (hazard ratio, 0.640; 95% confidence interval, 0.463-0.883, P = 0.007) than Early group in pairwise comparisons. We depicted the incidence of major adverse cardiovascular event (MACE) by delayed time as a quadratic curve and found the bottom appeared at day 14. Conclusions The delayed PCI time varied in the real-world practice, but undergoing operations on the second week after STEMI had greater survival benefit and less adverse events for whom without early reperfusion and hemodynamic instability.