Abstarct: The growing demand for urban development and land scarcity has led to the widespread construction of high-rise buildings. Accurate seismic vulnerability assessment is essential given their critical importance and sensitivity to seismic events. Recent advancements in earthquake engineering highlight the need to incorporate soil–structure interaction (SSI) in performance evaluations to predict structural behavior better. This study evaluates the probabilistic seismic performance of a 33-story reinforced concrete frxame–tube tall building with core shear walls and a pile foundation, designed according to the Iranian seismic code. Nonlinear Incremental Dynamic Analysis (IDA) was conducted in MIDAS software under Fixed baxse and SSI conditions. Scaled ground motions ranging from 0.1g to 1.5g were applied to develop IDA and fragility curves. The peak inter-story drift ratios determined seismic fragility at four damage states: Slight, Moderate, Extensive, and Complete. Results reveal that the building exhibits increased vulnerability under SSI conditions compared to the Fixed baxse model. Moreover, structures subjected to long-period earthquakes were found to be more susceptible than those exposed to short-period motions. The findings underscore the significance of incorporating SSI effects in the seismic assessment of high-rise buildings for more realistic performance predictions and risk-informed design strategies.