The anatomical study of pattern distribution of extratemporal branches of facial nerves was performed in 50 Thai cadavers regardless of age and sex. The distances from exocanthion to otobasion superius (ex-obs), lateral palpebral line to anterior border of parotid gland, lateral palpebral line to the point that the zygomatic branch anastomosis with buccal branch and the distance from lateral eyebrow to temporal branch were measured. The course of marginal mandibular branch caudal to the lower border of mandibular angle was observed and the distance from the nerve to the lower border of the mandible was also measured. The data was recorded by mean, range and standard deviation. The pattern of distribution was recorded by drawing and photographing the specimens. The mean length of ex-obs was 7.24 ± 0.60 cm. The distances from lateral palpebral line to anterior border were 3.95 ± 0.96 cm. and 1.04 ± 0.38 cm., respectively. The distance from lateral palpebral line of parotid gland was 54.54 ± 11.35% of ex-obs length. 57.14% of the marginal mandibular branch was coursed caudal to inferior border of mandibular angle. The mean distance was 0.91 ± 0.22 cm. There was 1% of marginal mandibular branch coursed caudal to mandibular border where it reached the facial artery. The mean distance from lateral eyebrow to temporal branch was 1.78 ± 0.14 cm. The patterns distribution of extratemporal branches of facial nerves were classified into twelve types. Type I - VIII were the same as McCormark’s report. The percentages of type I-VIII were 1, 5, 8, 4, 15, 22, 14 and 13 respectively. In this study we found four new types which were type IX - XII. The percentages of these types were 6, 3, 5 and 4 respectively.
