When the polar adventure ship is launched, tugs are used to push the ship up to the dock. Because the cruise ship structure is very weak, it is necessary to check the structural strength of the pushing. In order to analyze the structural strength of the cruise ship side structure under the action of the jacking force, the structural stress of the side stern under the action of the jacking force is calculated based on the finite element simulation method. Secondly, the stress of the target beam under one span, three spans and five spans is calculated by simplifying the calculation of the beam system. Through comparative analysis, it can be concluded that the more spans considered in the calculation of the beam system, the lower the normal stress value in the X direction is. When the span of the beam system reaches five spans, the difference between the calculated results of the beam system and the finite element calculation value is only 2%. Therefore, in the pushing calculation, a five-span beam model can be established instead of finite element calculation to obtain the results quickly and ensure a certain calculation accuracy.