Historical masonry buildings that cover a large area with irregular geometric layouts do not display sound behaviors against earthquakes. Stresses, due to torsional moments in particular, occur as a result of either different heights or irregularities in plan and unbalanced mass distributions. Accurate analytical modeling during finite element analysis is of great significance for a reliable interpretation of the analysis results. In this study, two different loadings are applied on an analysis model of Kucuk Mustafa Pasha Bath. The first loading covers the analysis due to gravity loads while the second involves the loading due to ground movements defined by the earthquake spectrum. By means of these analyses, the performance of the building under the effects of earthquake is examined. In the interpretation of the results, due to the irregular mass distribution because of the uneven plan geometry and changing heights in the building, the importance of analytical modeling technique during the analyses of historical masonry buildings is emphasized.