In this paper, the cantilever piezoelectric energy collector is taken as the research object, aiming at the problem that there existed a deviation of the velocity frequency response function(VFF) of the distributed parameter model derived by Erturk in the range of 0~20 Hz during the simulation, a VFF modification method is proposed in this paper. First, the derivation of the velocity frequency response function with a tip mass of the distributed parameter model is introduced. Then through the simulation and analysis of VFF in the range of 0~20 Hz, it is found that the reason for the main error is the first term of VFF expression, thus the sine function with parameter α introduced to reduce the error. Considering that the introduction of the sine function led to the error of the second term of VFF, the tangent function with parameter β was introduced to reduce the error. Finally, the optimal range of α and β was determined by error analysis, and an example is analyzed. The results show that the velocity frequency response of the modified distributed parameter model is consistent with the experimental results.