Objective To investigate the relationship of the location of nerve compression and different type of trigeminal neuralgia.Methods Twenty-one patients with typical trigeminal neuralgia and 16 patients with atypical trigeminal neuralgia were treated by micro-vascular decompression.The position of the responsible vessels was probed during operation.Results Compared with atypical trigeminal neuralgia group, the compression rate of trigeminal root entry/exit zone (REZ) in typical trigeminal neuralgia group was significantly higher(P<0.01).The compression rate of trigeminal REZ which oppressed by artery in typical trigeminal neuralgia group was significantly higher than that in atypical trigeminal neuralgia group ( P<0.01 ) .Conclusions The responsible vessels in typical trigeminal neuralgia patients is mostly located in the trigeminal REZ, and the responsible vessels is mostly not located in other location in the trigeminal REZ.The responsible vessels oppress REZ is closely related to types of trigeminal neuralgia.