Knowledge of the normal dimensions and local anatomy of the internal acoustic canal (IAM) is necessary during evaluation of temporal bone trauma, congenital anomalies, affecting the individual nerves, and some neuro-otologic surgeries. The purpose of this study was therefore to characterize the anthropometry of the IAM. We made the following measurements in 14 normal temporal bones of Iranian male skulls from individuals 35 to 60 years of age (average of 50): Height and width of the middle portion of the IAM (mean 4.04 and 3.69mm), Height and width of the fundus of the IAM (mean 2.86 and 2.43mm), inferior and superior length of the IAM (mean 8.39 and 10.75mm).This study provides baseline information that maybe used to evaluate the congenital anomalies of the IAM. These data may also be helpful in the presurgical evaluations of the patients undergoing surgeries involving the IAM