Objective To investigate the microanatomic and surgical exposure of supraorbital extradural approach to cavernous sinus under endoscope, so as to provide the microanatomic basis for clinical neurosurgery. Methods Twenty fresh cadaver heads were studied using 4 mm 0° and 30° endoscopes to develop a surgical approach and identify surgical landmarks. Results The endoscopic supraobital extradural approach could be divided into 3 stages: entry into the extradural anterior cranial fossa, exposure of the middle cranial fossa and periorbita, and exposure of the superior and lateral cavernous sinus. This approach could expose superb views of the cavernous sinus microanatomy especially through the Dolence triangle, Parkinson triangle and Mullan triangle. Conclusion Endoscopic supraobital extradural approach offers excellent microanatomy of the cavernous sinus with minimal invasiveness, which is worthy of introduction.