Water-skipping is a kind of water skimming flight mode which includes the process of touching and leaving water surface， and its application to the design of a new trans-medium vehicle can effectively improve the anti-ship penetration capability of flight vehicle and its own survival capability. Because the water-skipping of moving body involves a variety of kinematic parameters such as velocity and attitude angle， the kinematic mechanism is complex. For a full-size trans-medium vehicle with complex shape， it needs to study a large number of working conditions to obtain the effects of initial value of different kinematic parameters on the water-skipping process by finite element simulation and flight test analysis， thus the workload is very heavy. To apply a simple scaled-down plate moving body to the water-skipping simulation analysis and experimental design， the predictability of the fluid similarity principle on the kinematic characteristics of the water-skipping process is verified. Based on the fluid-structure interaction method described by arbitrary Lagrange-Euler and the gliding theory of simple two-dimensional plate， the water-skipping kinematic characteristics of the complex trans-medium vehicle and the simple plate moving body are investigated， respectively， the skippable area of the two moving bodies， which contain multiple influence parameters， is analyzed and determined， and the relationship between them is further explored based on the similarity principle. The results show that the skippable area distribution of the proposed trans-medium vehicle is almost independent of the initial flight path angle， and the skippable area expands with the increase of the initial velocity and eventually stabilizes； the simple plate model can be used for model test and simulation analysis， and new ideas for engineering solution in the preliminary design phase of a trans-medium vehicle can be provided by using similarity principle to inversely estimate the skippable area of the complex trans-medium vehicle.