Abstract: To address the limitations of current experimental and numerical studies on the propagation of gas-coal dust explosion shock waves, which are mostly confined to small-scale laboratory pipelines or local roadways, this study adopted a segmented relay simulation method, dividing the simulation process of gas-coal dust explosion shock wave propagation into two sections: the gas-coal dust explosion section and the shock wave propagation section. A geometric model was established according to the actual roadway size of a mine, and the propagation law of gas-coal dust explosion shock waves under different explosion conditions was simulated using Fluent software. The results showed that: ① the explosion equivalent had a certain influence on the overpressure variation curve of the explosion shock wave and a significant influence on the peak overpressure. The peak overpressure increased markedly with increasing explosion equivalent. In the explosion section, the peak overpressure first increased and then decreased due to the energy accumulation effect, while in the shock wave propagation section, the peak overpressure decayed in the form of a power function, and the larger the explosion equivalent, the faster the overpressure attenuation. ② When gas-coal dust explosions occurred at different locations, the propagation path length, roadway size, and roadway connection type had no significant effect on the overpressure variation curve. The overpressure curve along the propagation path exhibited a dynamic evolution from "multi-peak oscillations → single peak → multi-peak oscillations". However, these factors played an important role in overpressure attenuation: the longer the propagation path and the more the branch roadways, the more significant the attenuation, indicating that branch roadways had a good pressure relief effect. ③ Under different explosion locations and explosion equivalent conditions, the attenuation law of overpressure along the propagation path was generally consistent. The overpressure attenuation rate gradually decreased with increasing propagation distance. A larger explosion equivalent resulted in a higher initial overpressure and a greater pressure gradient, leading to faster overpressure attenuation. The branch structure significantly promoted overpressure attenuation, with the most substantial attenuation occurring after the first open branch, while the attenuation magnitude of subsequent branches decreased successively.