<p>As a key physical quantity reflecting the dynamic characteristics of rocks, wave impedance is crucial for studying the deformation and failure mechanism of rocks under dynamic loads. To investigate the influence of rock wave impedance on stress wave propagation and rock mechanical response in the split Hopkinson pressure bar (SHPB) experiments, the functional relationship between the dimensionless transmitted and reflected wave stress and the sample wave impedance in SHPB experiments is theoretically derived. For different waveform incident waves, a method of stepwise equivalent simplification of incident waves is proposed to study the influence of sample wave impedance and incident wave rise time on transmitted and reflected waves. On this basis, from the perspective of stress wave propagation and stress-bearing process, the influence mechanism of rock sample wave impedance on its dynamic mechanical response in SHPB experiments is analyzed. The research results show that: (1) Both sample wave impedance and incident wave rise time have a significant influence on stress wave propagation. (2) Under the same amplitude incident wave, the slower the rise time of incident wave, the smaller the loading rate during dynamic loading process of sample, and the smaller the strain rate of sample. (3) Under the same incident wave, the magnitude of sample wave impedance will affect its strain rate history and stress history, which in turn affects its dynamic mechanical behavior. The research results have certain guiding significance for the development of SHPB experimental technology and engineering practices such as rock failure and protection under dynamic loads.</p>