Purpose Extensive resection probably confers a modest survival advantage in patients with glioblastoma. Studies have revealed the positive effects of intraoperative stimulation mapping (ISM) on the extent of resection, but no consensus for contribution of intraoperative stimulation mapping is reached. Methods This retrospective study enrolled two groups of patients who underwent surgery for motor-eloquent glioblastoma: the non-ISM group of 57 patients (surgery in 2008–2013) and ISM group of 13

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... atients (surgery in 2014–2015). The two groups and subgroups based on resection extent and postoperative additional neurological deficit were compared using Kaplan–Meier analysis and the log-rank test. Results Gross or near total resection (≥ 90% resection quality) was significantly more common in the ISM group than the non-ISM group (76.9% versus 24.6%; p = 0.001). The extent of resection was also significantly greater (90.5% ± 15.6% versus 64.6% ± 29.2%; p = 0.002). The neurological outcome in the ISM group was thus superior, but the two differences were not significant. The median progression-free survival time was significantly longer in the ISM group (22.0 ± 5.1 months vs 8.0 ± 1.0 months; p = 0.037) but a significant difference was not indicated in median overall survival time (22.0 ± 8.4 months vs 16.0 ± 2.2 months; p = 0.167). Conclusion ISM was discovered to lead to higher quality of resection and delayed recurrence. The neurological outcome and median overall survival time in the ISM group was thus superior, but the two differences were not significant. Trial registration number (for clinical trials) Nil