Microsurgery for space-occupying lesions in the cerebellopontine angle (CPA) region serves as a core challenge in Neurosurgery that balances lesion resection and neurological function preservation. Lesions such as acoustic neuromas, cholesteatomas, meningiomas, and schwannomas, due to their close proximity to the cochlear nerve, facial nerve, and brainstem, pose significant challenges to the protection of auditory function during surgery. While aiming for total tumor resection, the maximum preservation of facial nerve and cochlear nerve functions, especially hearing function, has become a core goal of modern neurosurgery. Brainstem auditory evoked potential (BAEP) and electrocochleogram (ECochG) are two key techniques for intraoperative monitoring of the auditory pathway, each with its own advantages and disadvantages. In recent years, the combined monitoring protocol of BAEP and ECochG, with complementary advantages, provides surgeons with more comprehensive, real-time and precise information on auditory pathway function, enables early warning and precise localization of injury, and significantly improves the postoperative rate of useful hearing preservation. It has become an indispensable auxiliary tool for refined and functional surgery in the CPA region. This article systematically reviews the technical principles and implementation schemes of combined BAEP and ECochG monitoring, with emphasis on analyzing its application value and characteristics in the resection of space-occupying lesions of different pathological types in the CPA region, aiming to provide references for improving the quality of life of patients.