The work aims to investigate the cooling effect of the spiral flow channel in a central impression cylinder of satellite flexographic press during printing process. With double-walled central impression cylinder as the research object, the velocity field and temperature field of cooling water within the channels, and the temperature field of the outer wall of the impression cylinder were analyzed through numerical simulation. The simulated results were compared with those of a double-walled cylinder without spiral flow channels. The effect of rectangular cross-sectional geometries of the spiral flow channel on the axial temperature difference of the cylinder surface was discussed. The cylinder with the spiral flow channel had a lower surface temperature and a smaller temperature difference of 4.2 °C. The spiral flow channel with a greater height/width ratio in cross-sectional dimensions contributed to a smaller axial temperature difference at the same inlet flow velocity. When the inlet flow velocity of the cooling water was 2.5 m/s, and cross-section height/width ratio of the flow channel was 0.6, the axial temperature difference on the surface of the cylinder was 2.46 °C. The rectangular spiral flow channels with a greater cross-section height/width ratio are beneficial to reducing the surface temperature difference of the central impression cylinder, having a better cooling performance.