<p>The deformation characteristics of living fish are particularly important for efficient and accurate numerical calculations. This is because for the cases of calculation of fluid-solid coupling of deformable bodies, the solid deformation parameters need to be substituted into the numerical iteration as the most basic input parameters. However, due to the lack of key information on the deformation of living fish, many previous research works could be conducted only based on simplified deformation theory models. This will lead to the introduction of artificial deviations, and the degree of deviation cannot be estimated. Therefore, this paper introduces the user defined function to take the real deformation characteristics of living zebrafish collected from the experiment as input parameters and substitutes them into the numerical calculation. It also gives quantitative results on the evolution law of the zebrafish’s wake vortex and the surface force distribution characteristics. By comparing experimental observations, it is clearly illustrated that the numerical calculation method introduced in this paper by introducing real fish body deformation data could effectively simulate the small angle turning process of zebrafish. The changing characteristics of the force acted on the fish body within one period could also be performed. This would be helpful for further discussion on the control mechanism of fish wake vortex and the influence law of key control parameters of fish swimming.</p>