Background To accurately assess the treatment effect of paclitaxel drug-coated balloon (DCB) angioplasty is essential for intracranial atherosclerotic disease (ICAD) patients. This study aimed to investigate the clinical feasibility of high-resolution vessel wall MRI (HR-VWI) in assessing ICAD with DCB angioplasty. Methods Forty-five patients with intracranial atherosclerotic stenosis ≥ 70% confirmed by digital subtraction angiography (DSA) underwent HR-VWI before and after DCB angioplasty. Postoperative follow-up was performed after 6 months (±1 month). The differences of pre- and postoperative HR-VWI characteristics, including vessel and lumen area at maximal lumen narrowing (MLN), plaque area and length, degree of stenosis, plaque burden (PB), remodeling index, and plaque enhancement amplitude (PEA) were compared. The relationship between stenotic rate obtained using HR-VWI and DSA was evaluated. Each HR-VWI characteristic and clinical factor before DCB angioplasty was separately evaluated for the association with postoperative restenosis. Results After six months, lumen area of MLN, plaque length and area, degree of stenosis, PB, and PEA showed a significantly difference relative to the value before DCB angioplasty (all P < 0.05). Spearman correlation coefficients of 0.865 and 0.932 were revealed between DSA and HR-VWI regarding the stenotic rate analysis pre- and post-operation (both P < 0.05). ROC analysis showed PEA, plaque length, and PB before DCB angioplasty separately provided robust prediction of postoperative restenosis (area under the curve = 0.909, 0.814 and 0.743; all P < 0.05). Multivariable analysis revealed that PEA was an independent predictor of prognosis. Conclusions The HR-VWI can accurately assess the treatment effect of DCB and robustly predict prognosis.