The present postmarketing surveillance investigated the safety and efficacy of clopidogrel for prevention of cardiovascular events following percutaneous coronary intervention (PCI) in a real-life setting with a large patient population. This study included patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) who had unstable angina, and patients with non-ST-segment elevation myocardial infarction, stable angina, and old myocardial infarction (SA/OMI), or ST-segment elevation myocardial infarction (STEMI). For safety assessment in 4049 patients, the incidence of adverse drug reactions (ADR) and bleeding adverse events (AE), and for efficacy assessment in 3900 patients, that of major adverse cardiovascular events (MACE) and MACE and cerebrovascular events (MACCE), was calculated in the primary diagnosis groups (NSTE-ACS, SA/OMI, or STEMI). ADR incidence did not significantly differ by group (10.1, 11.6, and 12.2 % in the NSTE-ACS, SA/OMI, and STEMI groups, respectively). Cumulative ADR incidence was highest in the STEMI for 52 weeks. Both total and cumulative bleeding AE incidences were higher in the SA/OMI group (5.9 and 6.8 %, respectively) than in the other groups (3.5 and 3.8 % in the NSTE-ACS, 3.6 and 4.5 % in the STEMI). The MACCE and MACE incidence rates were higher in the STEMI groups than in the other groups. In conclusion, we did not find additional concerns regarding safety and efficacy of clopidogrel in patients who have undergone PCI, regardless of their diagnoses.