AbstractContext: Bladder injury and perforation is a major problem encountered during transurethral resection of bladder tumor (TURBT) under spinal anesthesia which can be overcome using obturator nerve block. Aims: To evaluate obturator nerve block (ONB) using peripheral nerve stimulator during TURBT. Subjects and Methods: Twenty adult male patients underwent TURBT under spinal anesthesia. ONB was performed with peripheral nerve stimulator. Data was assessed in terms of primary endpoints - the occurrence of obturator jerk, injury or perforation of bladder, and surgeon satisfaction in terms of ability to resect the tumor, number of surgical interruptions and number of blood transfusions required. Results: In our study, there was reduction in obturator jerk but not complete abolition, during resection of bladder tumor. Bleeding was observed, however no bladder perforation occurred. Conclusions: We conclude that ONB, when administered along with spinal anesthesia for TURBT, is feasible, simple and safe method of anesthesia to overcome adductor contraction. ONB with peripheral nerve stimulator is more precise and extremely efficient, although not absolute during TURBT.