Masonry construction has been the most popular form of building. Protection of masonry heritage structures against earthquakes is a strategic research topic. Architectural history includes many old masonry structures, so keeping them safe from collapse is essential. Researches about the assessment of masonry structures have become more frequent in the last few decades. However, the results about the seismic behaviour of masonry structures are still limited, and further research is needed. Pushover analysis is a very common approach to assess the seismic performance of structures subjected to seismic loads. The main objectives of this research are to evaluate the seismic performance of Trani's Cathedral Bell Tower in accordance with the Applied Technology Council (ATC-40) and determine the target displacement of the tower using the pushover analysis method. The finite element software ABAQUS was used to perform a numerical analysis under the expected loads. The numerical results, such as stresses, deformations, cracks, and pushover curve indicate the overall stability and safety of the structure in its current state. Finally, the developed model can predict the locations of cracks and provide an efficient tool for the assessment of existing masonry structures. The results showed that the investigated tower satisfied the seismic loads.