At present, it is believed that intravenous (IV) infusion of lidocaine can inhibit hyperalgesia, relieve postoperative acute and chronic pain, and accelerate the rehabilitation of patients. However, studies of its effects on necessary electrophysiological monitoring during neurosurgery are few, and the results are controversial. This study assumes that the propofol-remifentanil based anaesthesia combined with lidocaine in patients undergoing intraspinal tumour resection will not have adverse effects on motor-evoked potentials (MEPs) or somatosensory-evoked potentials (SEPs). Study Design and Methods: This is a prospective, randomized, placebo-controlled double-blind trial. A total of 96 patients undergoing intraspinal tumour resection will be randomly allocated to lidocaine and placebo group. The lidocaine group will receive IV lidocaine during anaesthesia, while the placebo group will receive the same dose of normal saline with the same infusion rate and infusion time, and the anaesthesia procedures of the two groups will be the same. All patients will be monitored the MEPs and SEPs of all four limbs during operation. The primary outcome will be the MEP amplitudes of both upper limbs at the end of operation. The secondary outcome measures will be the other electrophysiological parameters at the end of operation, the incidence of alert events for all four limbs, and the incidence of false positive events. Discussion: The purpose of this study is to evaluate the effects of IV infusion of lidocaine on SEPs and MEPs during intraspinal tumour resection to determine whether electrophysiological monitoring can accurately reflect the integrity of nerve functions while infusing lidocaine and to explore the possibility of lidocaine use during intraspinal tumour resection as an anaesthesia option.