In order to study the influence of key parameters of propeller diameter trimming on vibration characteristics, the vibration analysis software for propeller diameter trimming is developed. With the finite element theory, based on the Qt platform, and combined with the related modules of MATLAB and ANSYS, the hybrid programming is conducted to complete the development. Taken Propeller 4382 for example, the numerical prediction of modal frequency is conducted, and the error is less than 6.0% compared with the literature results, which proves that the program and calculation results of the software are reliable. The software can provide theoretical guidance for determining the propeller diameter trimming scheme with the optimal vibration characteristics under the ship-machine-propeller matching, and is of good engineering application value.