Abstract: Floating ring seal is an important sealing unit in aero-engine, and its internal waveform spring provides axial support force, which is the key to the normal operation of floating ring seal. This paper establishes an elastic-plastic finite element model of the wave spring based on the material stress-strain test data, calculates the linear stiffness and linear compression limit of the wave spring under different structural parameters, material parameters and operating parameters, and analyzes the influencing factors of the wave spring elasticity and the influencing law under typical parameters. A multi-factor mathematical model was constructed using the response surface method to compare the degree of influence of each structural parameter on the linear stiffness and constant stiffness limit ratio. Then, the research results were verified by experiments. The results show that the influence of each parameter on the linear stiffness and constant stiffness limit ratio of wave springs is in the following order from the strongest to the weakest: wall thickness, number of waves, width, modulus of elasticity. The constant stiffness limit ratio of wave springs decreases with the increase of the stiffness. For the single-layer wave springs, under different opening forms and the same other structural parameters, the values of linear compression stiffness are as follows from the largest to the smallest: closed-type, lap-type, open type. In actual working conditions, in order to ensure that the waveform spring can play an effective role, it is recommended to control the compression amount of the wave spring in the working state between 5% and 65% of the wave height.