The purpose of this study was to identify the branching patterns and the distribution of the cartical branches of the middle cerebral artery (MCA) in 100 cerebral hemispheres of Korean adults The intracranial arteries were perfused with red latex compounds The teintory of the MCA was divided into 12 areas orbtiofrorital, prefrorital, precentral, central, anterior parietal, posterior parietal, angular temporo-occlpltal postenor temporal middle temporal, anterior temporal and temporopolar Branching pattern of the mam trunk of the MCA was divided into five types Type I a smgle-trunk type of MCA In 34% of cases, Type II bifurcation (57%), Type in trifurcation (5%), Type IV quadnfurcation(I%), Type V two MCAs ongmated from the internal carotid artery (3%) The MCA of the bifurcation type was cla<;slfled into equal bifurcation (20%), supenor trunk dommant (11 %) and mfenor trunk dommant (26%) according to the cortical area The supenor trunk of the equal bIfurcation supphed from the orbltofrontal to postenor parietal area The outer diameter of the mam trunk of the MCA was 3 15±0 52 mm on average The anatomical types of the MCA were discussed With the related symptoms in disease of the MCA