Extratemporal facial nerve is divided into five branches that have their own significant roles in facial expression. Even though there have been many descriptions on its exact anatomy and relations between its branches through cadaver dissection, its course, ramification and connection between neighboring branches are all quite variable. And so, familiarity of its accurate anatomy is prerequisite for the operator to prevent accidental or unexpected nerve injury during operation. In this study, the intraoperative mapping study was done to obtain the exact anatomical data by drawing the exposed facial nerve branches in life size during the operation of parotidectomy, excluding the observational error that could be caused in cadaver studies. 27 sides of facial nerves among 44 patients were completely dissected after parotidectomy operation. The patients had benign or malignant lesion of parotid or cheek and, vascular malformation was the most prevalent cause of parotidectomy. After the exposure of all 5 branches of the facial nerve, the intraoperative mapping was done with a translucent paper in the operation field and anatomical observation was followed such as counting of ramification, interlinking between branches, course of branches, classification of branching type. With regard to the connection between branches, it was most in zygomatic to buccal connection (88.8%) and least in buccal to mandibular connection (11.1%. Connections between branches in child and female were more than in adult and male. In the aspect of ramification number of branches, female (mean 15.8) had more branches than man (mean 10.5). In each branch, the buccal branch had the most ramifications (mean 3.8) and the mandibular branch had the least (mean 1.2) on the contrary. Type IV, V and VI were prevalent in branching classification and the frontal branch had an especially variable course that ran inside to the temporal hairline in 7 dissections (25.9%). To prevent Frey°¯s syndrome and postoperative depression deformity after parotidectomy, buccal fat / dermis fat graft or flap / superficial temporal fascia flap or skin flap were appropriately selected for covering the exposed facial nerve according to the indications. Acquaintance of accurate course of frontal branch can relieve the risk of accidental nerve injury during the operation such as harvesting the superficial temporal fascia.. Female has more ramification number and this anatomical finding would be related with more delicate and variable expression than male. The classification of branching types can be insignificant in the aspect of its quite variability.