OBJECTIVE: The neurosurgical management of dorsal pontomesencephalic junction lesions is inherently complex and challenging. In this study, we introduce a novel endoscopic technique for the resection of such lesions: the contralateral occipital interhemispheric transtentorial superior transvelar (cOTT-STVel) approach. METHODS: A meticulous dissection of five formalin-fixed cadaveric specimens was conducted to simulate the cOTT-STVel approach, with a focus on exposing the pontomesencephalic junction and the upper fourth ventricle. Each key anatomical landmark was thoroughly evaluated. Furthermore, we present a detailed clinical case demonstrating the effective and safe removal of a pontomesencephalic cavernous malformation (CM) utilizing this innovative surgical approach. RESULTS: No cortical veins draining into the superior sagittal sinus were found in the field of view behind 1 cm superior to the lambdoid suture. The critical surgical procedures included: a unilateral occipital craniotomy, identification and lateral incision of the tentorium, arachnoid dissection to reveal the cerebellomesencephalic fissure, the superior medullary velum exposure and openning to unveil the upper fourth ventricle and the dorsal pontomesencephalic junction. Utilizing this surgical approach, we achieved a complete resection of a CM located at the dorsal pontomesencephalic junction. The surgical trajectory provided ample exposure, enhancing the precision of the surgical manipulation and offering a significant advantage in visualizing the contralateral lateral region. CONCLUSION: This study validates the practicality and efficacy of the endoscopic cOTT-STVel approach for resection of pontomesencephalic CMs. This approach affords optimal entry to the upper fourth ventricle and the dorsal mesencephalopontine junction, strategically broadening the surgical reach laterally via a pioneering "cross-court" corridor.