The foramen tympanicum is an anatomical variation that is created in the tympanic plate of temporal bone during the first year of life. The tympanic plate grows and foramen tympanicum is gradually closed by about the fifth postnatal year. However, due to a defect in normal ossification, foramen tympanicum sporadically remains throughout life. The construction of a shopping center in Tabriz, northwest of Iran, led to the discovery of an Iron Age cemetery (1500-500 BC). Several tombs have been uncovered below one meter of sterile soil so far and a thick level of architectural debris from the medieval city has been discovered. Up to now, no bioarchaeological data has been gathered about the burials in this area. Thus, the present study aimed to evaluate the prevalence of foramen tympanicum in this area. In this study, 45 skeletons were studied and the prevalence of this foramen was about 4.4% bilaterally. We also reported on two babies with fused and un-fused squamotympanic fissure. The persistence of this foramen is a possible risk factor for otologic complications after arthroscopy of the temporomandibular joint and salivary gland fistula through this foramen. The closure of this foramen could be also used for age estimation in sub-adult individuals. The incidence of this trait in this study was similar to other available studies on modern skeletons.