In order to solve the problem of confusing the difference between rhombus structure and bridge structure in the static modeling of traditional bridge amplification mechanism, and ignoring the deformation of rigid link, the amplification factor is calculated by Euler-Bernoulli beam theory and energy conservation theory, and the accuracy of each theoretical model is verified and compared by using ANSYS Workbench. In addition, the radial basis function (RBF) neural network model and multi-island genetic algorithm (MIGA) are used to optimize the parameters of the bridge amplifier. The results of simulation analysis show that the amplification factor calculated by using Euler-Bernoulli beam model and energy conservation law is the closest to the simulation value. The optimized amplification factor increases by 16.0% and the natural frequency increases by 19.7%. It can be seen that the proposed theoretical model and optimization method are effective.