Abstract: According to the distribution and structural characteristics of components on an airborne PCB, an equivalent modeling method of PCB dynamic characteristics based on the local mass stiffness equivalence of components is proposed. This method is based on the original geometric dimensions of the PCB substrate. The stiffness and mass of the components are equivalent to the connection between the substrate and the components to equivalent the impact of the components on the overall substrate on the actual PCB. Based on the modal test, the Young's modulus and Poisson's ratio of the PCB substrate and the equivalent modeling area are obtained. Then the obtained equivalent model is used in the finite element simulation to calculate the modal frequency and mode shape of the numerical calculation of the equivalent model; and the results are compared with the modal test results. The results show that the equivalent modeling method meets the engineering requirements, and it provides a reference idea for rapid equivalent modeling to obtain dynamic characteristics of the similar PCB products in the future.