The seismic vulnerability of reinforced concrete buildings is an essential issue in earthquake-prone areas. Soil amplification, i.e., the increase in ground motion caused by the geological and geotechnical properties of the underlying soil, significantly impacts the seismic response of buildings. Soil amplification can significantly affect the distribution of seismic forces and deformations within buildings; therefore, soil conditions must be considered during the design and evaluation of structures. This study focuses on how soil amplification affects the seismic vulnerability of reinforced concrete buildings, with the aim of better understanding the complex relationship between soil dynamics and building behavior. Geotechnical site data are considered to determine site-specific soil properties such as soil types, shear wave velocity, and soil stratigraphy. Seismic hazard analysis is used to predict ground motion, and SAP2000 is used to simulate the dynamic behavior of a 5-story RC frame building. The building's response to seismic forces is estimated through a time history analysis of amplified ground motion. Finally, the probability of damage to the RC frame building has been estimated due to the amplified ground motion. This research contributes to developing more effective strategies for mitigating the seismic vulnerability of RC frame buildings subjected to soil amplification by influencing building codes, design practices, and risk assessment methodologies.