Objectives The prognostic value of hs-CRP levels at pre and post percutaneous coronary intervention (PCI) remains debated. We hypothesized that a higher degree of inflammatory response, as measured by the change in hs-CRP levels after PCI with drug-eluting stent (DES), would be related to a higher risk of proliferative neointimal hyperplasia (NIH) and poor long-term clinical outcomes. Methods We performed PCI with a single DES in 144 consecutive stable angina patients (81 men; 60.7짹9.3 years of age). The plasma hs-CRP level was serially measured before and at 24, 72 hours after the PCI. The difference (��) of hs-CRP levels between baseline and each stages after intervention was calculated. An angiography and IVUS study were performed at pre, post PCI and 9 months after the PCI in all patients. Median clinical follow-up duration was 44.6짹11.0 months Results No relationship was found between hs-CRP value at baseline and NIH proliferation (P=.974). A significant positive correlation, however, was noted between the hs-CRP value and NIH proliferation at 24 hr (r=.308, P=.002) and 72 hr (r=.286, P=.004) after PCI. Moreover, a significant positive correlation was noted between the �� hs-CRP value and NIH proliferation at 24 hr (r=.325, P=.001) and 72 hr (r=.302, P=.002) after PCI. The �� hs-CRP value at 24 hr after PCI was higher in patient with restenosis compared to without restenosis (14.0짹19.2 vs. 8.3짹10.3 mg/L), but there was no statistical significance (P=.259). And the �� hs-CRP value at 24 hr after PCI was higher in patient with major adverse cardiac event (MACE) (9.3짹17.4 vs. 5.7짹9.8 mg/L) during follow-up duration compared to without MACE, but there was also no statistical significance (P=.441). Conclusions The inflammatory response, as measured hs-CRP values, predict NIH proliferation at 9 months after PCI with DES but not long-term clinical outcomes.