Objective: The objective of this study was to estimate the entrance surface radiation dose to the thyroid region in a computed tomography (CT) brain scan.Methods: Unfors Multi-O-Meter equipment was used to measure the entrance surface at the thyroid region of adult patients ranging from 18 to 70 years of age. A total of 115 patients were included in the study based on convenience sampling. The Multi-O-Meter was kept at the thyroid region during the scan, and the values for entrance surface dose (ESD) were noted from its monitor after the scan was complete.Results: The obtained data were analyzed and violate normal distribution; therefore, the median and quartiles were computed. The overall median (Q1, Q2), ESD of the patients, was 1.335 (1.213, 1.529) mGy. The minimum and maximum dose values recorded were 1.015 mGy and 1.964 mGy, respectively.Conclusions: The result showed a significant amount of entrance surface radiation dose to the thyroid region while taking a brain scan. This data can be used for optimization of radiation protection while undergoing CT scans of brain to reduce exposure to thyroid region.