Abstract: Matching design of zero differential power shift steering transmission is carried out. In order to characterize the matching design of hydrostatic steering power flow, three important parameters were introduced, namely the kinematic design coefficient of steering power flow φ_v, the working pressure coefficient of hydrostatic steering circuit φ_p, and the hydrostatic steering power flow coefficient φ_w. Through theoretical and experimental analysis, the experimental results are reported. For high-speed tracked vehicles of light-or-medium-duty, a better steering performance is obtained when φ_v ranges from 3.6 to 6.0. For vehicles on cement road, it is recommended that φ_p should range from 0.65 to 0.80. And for basic type of vehicles on cement road, φ_w is recommended to be from 0.45 to 0.55. Based on series of successful matching design examples of steering power flow and experiments of prototype vehicles, this paper concludes that: if φ_v, φ_p and φ_w take the value ranges derived from the present study, a good performance of hydrostatic continuously variable steering system can be guaranteed.