Although balloon angioplasty for femoropopliteal artery lesions has been associated with restenosis rates of up to 60% at 12 months, the mechanism of restenosis has not been fully evaluated. The aim of this study was to evaluate the relationship between the vascular features observed on optical frequency domain imaging (OFDI) before and after balloon angioplasty of femoropopliteal artery lesions, and restenosis at 6 months. This study was a prospective multicenter single arm study. OFDI was performed before and after balloon angioplasty and plaque characteristics and vascular features, along with de novo lesions, were assessed. The primary outcome was the presence or absence of restenosis 6 months after balloon angioplasty. Residual platelet reactivity was assessed according to VerifyNow platelet reactivity units (PRUs). The number of patients completing 6 months of follow-up was 47, of which 14 had developed restenosis. Maximum thickness of the dissection flap (odds ratio (OR) 2.71; 95% confidence interval [0.9-8.0]; p = 0.071) and lesion length were identified as risk factors for restenosis (OR 1.015; 95% confidence interval [0.001-0.029]; p = 0.039). The mean PRU at the time of treatment in patients with restenosis was significantly higher than in those without restenosis (286.3 ± 82.6 vs. 208.5 ± 03.6, p = 0.026). Long lesions and major dissection on OFDI after balloon angioplasty for femoropopliteal artery lesions increase restenosis at 6 months. In addition, high residual platelet reactivity at the time of EVT may also be a risk factor for restenosis.Clinical Trial Registration Number UMIN000021120.