(1) This is an observation of the posterior parietal, gyrus angularis and posterior temporal arteries of the middle cerebral artery in 100 cerebral hemispheres of chinese adult. Of these arteries, the site of appearance, length, number of branches and their direction are observed, inner and outer diameters of the vessels and thickness of the vessel wall are also measured respectively.(2) Both posterior parietal and gyrus angularis arteries appear at the terminal end of lateral cerebral sulcus, the posterior temporal artery appears at the middle part of the lateral cerebral sulcus (58?4.94%) or at the terminal end (42?4.94%). Most of these arteries measure 1～3 cm in length.(3) Most of these arteries remain as a single stem, some of them branch into two and only a few of them branch into three.(4) The average outer diameter of the above-mentioned arteries is 1.11～1.25 mm, the average inner diameter is 0.93～1.03 mm, and the average thickness of their vessel wall is 0.09～0.10 mm.