Abstract: Objective: To measure the bony structure of petrous bone and explore relationship between the nerve and blood vessel around the tentorium cerebelli hiatus to provide the anatomical basis in subtemporal transtentorial approach. Methods: The highest point of the arcuate eminence was set as the base-point, the distance of the outer edge of foramen lacerum, hiatus canalis facialis and posterior border of the internal auditory foramen from the base-point in 15 cases(30 sides) were measured. The superior cerebellar artery, posterior cerebral artery, oculomotor nerve, trochlear nerve, trigeminal nerve and tentorium of cerebellum, and their relationship with tentorium cerebelli were observed in 10(20 sides) heads with subtemporal transtentorial approach. Results: The distances of the highest point of arcuate eminence from the outer edge of Foramen lacerum, hiatus canalis facialis and posterior border of the internal auditory foramen were(34.98±1.67)mm, (14.67±1.74)mm and(15.31±1.78)mm, respectively. The distance between the terminations of the labbe vein and STP(including transverse sinus, sigmoid sinus and rock junction of the sinus) was (24.60±5.82)mm, and the distance between the trochlear nerve into the free margin of the tentorium and posterior clinoid were(15.50±3.85) mm, respectively. Conclusions: Measuring the distances of the highest point of arcuate eminence from outer edge of foramen lacerum, hiatus canalis facialis and posterior border of the internal auditory foramen and detecting the tracks of superior cerebellar artery, posterior cerebral artery, oculomotor nerve, trochlear nerve and trigeminal nerve around the tentorium of cerebellum can improve the safety and successful rate in subtemporal transtentorial approach.