Objective: To study the frequency, clinical course, and functional outcome of perforator stroke (PS) resulting from elective stenting of symptomatic intracranial stenosis. Methods: Between September 2001 and November 2004, 169 consecutive patients with 181 symptomatic intracranial stenoses underwent stenting procedure at our institute. The preoperative perforator infarct adjacent to the stenotic segment (PIAS) on MRI was evaluated blindly. Patients who developed PS after stenting were enrolled. Each patient was assessed by an experienced stroke neurologist by neurologic examination and NIH Stroke Scale score every day until discharge and at day 30, and by modified Rankin Scale (mRS) score at the end of the first, third, and sixth month, and then at intervals of 6 months. Results: PS frequency was 3.0% (5/169 patients). The patients with preoperative PIAS had a higher frequency of PS and PS exacerbation, resulting from intracranial stenting (8.2%, 4/49), vs patients without preoperative PIAS (0.8%, 1/120; p = 0.031). Four PSs occurred during the procedure and one 10 hours after stenting. Four PSs reached the maximum deficit almost at once, and one after 2 hours from onset. All five patients were functionally independent (mRS <= 1) within 12 months. Conclusion: Patients with preoperative perforator infarct adjacent to the stenotic segment have a higher perforator stroke frequency after elective stenting of intracranial stenosis. Most perforator strokes occur during the procedure and reach the maximum deficit almost immediately. Functional outcomes are relatively good.