Historical masonry structures have an important place in cultural heritage. Therefore, maintenance of these structures should be made periodically to prevent natural and manmade hazards. The maintenance of these structures is divided into two parts, namely experimental and numerical applications. Experimental, especially non-destructive methods are crucial for increasing the knowledge level of historical structures. Also, experimental tests provide information data that is used in the modal updating process of numerical models. Thus, simulations that are impossible to make experimentally can be easily carried out with updated numerical models. In this paper, a historical masonry mosque called İskenderpaşa and its minaret is investigated by nondestructive experimental tests. Also, finite element models of both structures are created by ANSYS software. To obtain reliable numerical models, finite element model updating processes are made with the aid of experimental data. At the end of the study, the differences between natural frequencies are reduced from 18.6% to 4.9% for the mosque and from 15.2% to 4.8% for the minaret. According to the study, the modulus of elasticity is the most effective update parameter for both structures.