Based on the regenerative cooling technology of liquid rocket engine, the flow distribution characteristics of Z-type parallel channels were studied by numerical simulation method. The effects of channel number, channel section shape and entrance confluence structure on the flow distribution characteristics were analyzed. The results show that the non-uniformity coefficient of flow distribution decreases from 2.59% to 0.5% with the increase of the number of channels in the regenerative cooling system. Increasing the number of channels under the same flow area can effectively ensure the uniformity of flow distribution. The channel section shape has little influence on the non-uniformity coefficient of flow distribution, which is mainly reflected in the flow velocity distribution and heat transfer area in the channel, and the heat transfer effect of the trapezoidal configuration is better than that of the rectangular configuration. The entrance confluence structure is beneficial to the uniform of flow distribution. The research has a certain reference significance for the structural design of regenerative cooling channel.