Objective To explore the impact of a "one-week" staged multivessel percutaneous coronary intervention (PCI) versus culprit-only PCI on deaths and major adverse cardiac events (MACE). Methods We retrospectively analyzed 447 patients with multivessel disease who experienced a ST-segment elevation myocardial infarction (STEMI) within 12 h before undergoing PCI between July 26, 2008 and September 25, 2011. After completion of PCI in the infarct artery, 201 patients still in the hospital agreed to undergo PCI in non-infarct arteries with more than 70% stenosis for a "one-week" staged multivessel PCI. A total of 246 patients only received intervention for the culprit vessel. Follow-up ended on September 9, 2014. This study examined the differences in deaths from any cause (i.e., cardiac and noncardiac) and MACE between the two treatment groups. Results Compared to a culprit-only PCI treatment approach, the "one-week" staged multivessel PCI was strongly associated with greater benefits for 55-month all cause death [41 (16.7%) vs. 13 (6.5%), P = 0.004] and MACE [82 (33.3%) vs. 40 (19.9%), P = 0.002] rates. In addition, there were significant differences in the number of myocardial infarctions [43 (17.5%) vs. 20 (10.0%), P = 0.023], coronary-artery bypass grafting [CABG; 20 (8.1%) vs. 6 (3.0%), P = 0.021], and PCI [31 (12.6%) vs. 12 (6.0%), P = 0.018]. Patients undergoing culprit-only PCI compared to "one-week" PCI had the same number of stent thrombosis events [7 (2.8%) vs. 3 (1.5%), P = 0.522]. Conclusions Compared to a culprit-only PCI treatment approach, "one-week" staged multi-vessel PCI was a safe and effective selection for STEMI and multi-vessel PCI.