To explore the dynamic mechanical characteristics of coal-rock combined body (CRCB) load-bearing structures, impact tests were performed on CRCB specimens by using a separated Hopkinson pressure bar test device (SHPB) combined with an ultra-high-speed camera system. The propagation characteristics of stress wave , dynamic stress-strain relationship, energy evolution law, and distribution characteristics of CRCB crushed particles in the impact tests were analyzed. The obtained results showed that: with the increasing of impact velocity, the effect of the wave impedance difference between the CRCB specimens and incident bar on stress wave propagation is gradually weakened. The peak strength (sII) and peak strain of the CRCB had obvious strain-rate effects, the ratio of reflected energy decreases linearly. In addition, with increased impact velocity, the growth rate of the peak strength and ratio of absorbed energy gradually dropped, changing approximately as a power function. Macro-fractures of the CRCB mainly occurred at the coal or rock ends which is far away from the interface. When the stress at the crack tip is greater than the "weakened" coal or rock strength, the crack will continue to develop across the coal and rock interface. With the increasing of impact velocity and rock strength, the crushed coal particles gradually transform from massive to powdering, and the average size of crushed coal blocks decreases, which leads to a gradual increase in the fractal dimension of the CRCB specimens. Therefore, the monitoring and prevention of dynamic loads should be strengthened in the coal mines with thick and hard roofs.