There is controversy regarding the prognostic role of high-sensitivity C-reactive protein (hs-CRP) in predicting re-stenosis and major adverse cardiac events (MACE) in patients who undergo percutaneous coronary intervention (PCI) and stenting. To determine relationship between serum hs-CRP level and in-stent restenosis and 6-month MACE in patients who had underwent PCI and stenting. In this cohort study, 55 patients who presented to Imam Ali hospital for PCI and stenting were recruited consecutively. Serum hs-CRP level was measured upon admission to hospital and once again 24 hours after stenting. Six months later, the patients were followed by phone call and those who experienced acute coronary syndrome or with positive exercise tolerance test underwent coronary angiography. Upon presentation, only three patients (5.5%) had elevated levels of hs-CRP, but 24 hours after PCI, 45% had elevated serum hs-CRP levels. Six-month MACE (major adverse cardiac events) occurrence was 52.7%. Five patients (9%) developed restenosis of which mild stenosis (stenosis of 30-49%) was seen in 1.8%, moderate stenosis (50-74%) was seen in 1.8%, and severe stenosis (>75% stenosis) was detected in 5.4%. Diabetes mellitus (DM) was the only risk factor, which showed significant association with restenosis. There was a significant association between high LDL level and 6-month MACE (P= 0.001). All patients with in-stent restenosis experienced MACE. In addition, 66% of patients with elevated hs-CRP level experienced in-stent restenosis. There was a significant association between primary serum hs-CRP level and in-stent restenosis (P= 0.01). There was also a significant relationship between primary hs-CRP serum level and 6-month MASE (P= 0.02). PCI patients who have DM and abnormal LDL level are more likely to experience in-stent restenosis and consequent adverse events. These events are predictable through hs-CRP measurement after stenting.