The mosques are the most important pieces of Islamic culture in terms of their architectural and structural properties. Although, thousands of these mosques are still being used all over the world, many historical mosques are at risk in terms of seismic events. This study mainly focuses on historical Lala Pasha Mosque, which is located in the city center of Erzurum, Turkey. The main purpose of this study is to assess the structural behaviors and to investigate the architectural features and components of the mosque. The study was carried out in two main steps. Firstly, compression and three-point bending tests on the construction materials were conducted to determine the mechanical properties of the materials. In the second step, a three-dimensional finite element model of the mosque was developed and structural responses for the model were investigated by means of static and dynamic analyses. The results of the analyses show that the most critical parts of the mosque are the dome, pulley, and the supports of the main arch structures that carry the main dome. Additionally, the dynamic analyses prove that the most critical parts of the mosque are the sub-sections of the main columns, the window edges, and small domes.