Objective To define the anatomical characteristics of the insula and its relation with its surrounding structures that can lead to precisely design the microsurgical approaches of the insular region.Methods We analyzed the head data of 15 Chinese adult cadavers(30 hemispheres)fixed by 10% formalin.The relative anatomical landmarks of the insular region and the distance from the insula to its peripherally correlative structures were measured and described. Results The insula,being one of the paralimbic structures,constituted the invaginated portion of the cerebral cortex and formed the base of the sylvian fissure.The insula was covered and enclosed by the frontoorbitsl,frontoparietal and temporal opercula and the transmigrated part of the insula was the uncinate extreme capsule,the white matter region inferior to the insular cortex.The insula was adjacent to the external capsule,the claustrum,the internal capsule,the lenticular nucleus,the caudate nucleus and the thalamus.The insula separated the endbrain and the limbic structures like an inverted pyramid.Various unique anatomical features of the insula and the peripheral relations with the insula were determined by using the fiber dissection techniques.Conclusion A good understanding of the surgical anatomy,being extremely important for a neurosurgeon, can guide us to operate for such series of frequent and multiple diseases aS hypertensive intracerebral hemorrhage from the basal ganglia,the insular glioma and temporal lobe epilepsy in the neurosurgery.