The external carotid arteriogram is useful in the diagnosis of the head and neck disease, however the clinical utility has not been widely obtained in contrast with the internal carotid arteriogram of the intracranial lesion. It is partially because the distribution and shape of external carotid arterial branches are variable and complicated according to underlying mechanical factors in the normal condition, other partiality is the diagnosis of head and neck disease has been established easily by other clinical methods. Recently, the external carotid arteriogram is indispensable for the detection and the determination of the location and extension of head and neck lesion, especially in the case of early and small malignancy. For this reason amongst the normal distribution and variation of the external carotid arterial branches should be analysed to fulfill these purpose. At the Department of Radiology, Severance Hospital, College of Medicine, Yonsei University, the normal exte nal carotid arteriogram of the selected 105 cases in which the common carotid artery puncture had been performed for the internal carotid arteriography to evaluate the intracranial lesion, was conjoined. Therefore, the observation and analysis were limited to the shape and variable origination, the visualization and the direct distance from the root of external carotid artery of main branches. The results were as follows: 1. The bifurcation level of common cartery artery is C3-C4 in 52.8%, C2-C3 in 34.9% and C4-C5 in 10.4% (range;C2-C6). 2. The shape of external carotid artery from the root to the terminal bifurcation is variable, the straight and the curved shape are more frequent in the young adult before 5th decade, whereas the waved and the arch shape are more in the order age group. This suggest the arteriosclerotic change of blood vessel by aging process. 3. The superior thyroidal artery arises from the external carotid artery in 49.5% and from the common carotid artery in 23.8 . 4. The variable originations of the superior thyroidal, lingual and facial artery are the normal type of different origin in 78.3%, the ingofacial common trunk in 16.1%, thyrolingual common trunk in 3.7% and thyrolingofacial common trunk in 1.9%. 5. The ascending pharyngeal artery arises from the external carotid artery in 24.6%, from the occipital artery in 23.5%, from the root of occipital artery in 9.8%, and from the internal carotid artery in 1.6%. 6. The transverse facial artery arises from the external carotid artery in 27.9%, from the superficial temporal artery in 21.5% and from the maxillary artery in 10.5%. 7. The roentgen-anatomical shape of the maxillary artery are divided by the three part; 1st part of mandibular, 2nd part of pterygoid and 3rd part of sphenomaxillary. The most frequent shapes of each part of maxillary artery are the convex in 78.4% of mandibular, the oblique straight in 45.8% and the oblique convex in 35.2% of pterygoid and ill defined variable shapes ith the straight, the loop, and the arch of sphenomaxillary part. 8. The visualization rate of main branches of the external carotid arteriogram in the case of the performed common carotid arterial puncture is 69.5% in the posterior auricular artery, 70.5% in the cranial part of superficial temporal artery and 29.5% in the cranial part of middle meningeal artery. 9. The accessory middle meningeal artery observed in 18% of total 105 cases. 10. The distance from the root of external carotid artery to the origination of main branches is 1) in the range of 5-6cm in 33%, 6-7cm in 26% of the maxillary artery, 2) in the range of 1-2cm in 47.2% and 2-3cm in 25.2% of the occipital artery, 3) in the range of 1-2cm in 54% and 2-3cm in 25.2% of the facial artery and 4) in the range of 1-2cm in 55.6% and 0-1cm in 24.7% of the lingual artery in the high frequency. (range: 0-7cm). 11. The origination of middle meningeal artery is the range of 0.5-1cm in 57.6% from the root of ma..