PURPOSE: The incidence of early branches arising from the prebifurcation trunk of the middle cerebral artery is very high. However, no reports have addressed these early branches of middle cerebral arteries in the Korean population. The purpose of this study was to characterize these early branches in Koreans. MATERIALS AND METHODS: A retrospective review was performed on transfemoral cerebral angiograms performed at Jeju National University Hospital between May 2005 and March 2010. A total of 78 hemispheric angiogram sites met the study inclusion criteria. The digital subtraction anterior-posterior view was the basic image for the inspection, which was supplemented by a three-dimensional reconstructed image. RESULTS: We identified 86 early branches of the middle cerebral artery in 58 (74.4%) out of 78 hemisphere angiogram sites. The type of early branches in the 78 hemispheric angiograms included 20 angiograms that were classified as Group I (25.6%), 23 as Group II A (29.5%), 10 as Group II B (12.8%), 7 as Group II C (9.0%), 7 as Group III (9.0%), and 11 as Group IV (14.1%). CONCLUSION: The incidence of early branches arising from the prebifurcation trunk of the middle cerebral artery was found to be high in the Korean population and showed many morphological variations.