After manufacturing a structure, the assembly of structural components is often not as perfect as expected due to the immaturity of current engineering techniques. Thus the actual buckling load for an element is sometimes not consistent with that predicted in the design. For design considerations, it is necessary to establish an analytical method for determining the buckling load experimentally. In this paper, a dynamic method is described for determining the linear buckling loads for elastic, perfectly flat plates. The proposed method does not require the application of in-plane loads and is feasible for arbitrary types of boundary conditions. It requires only the vibrational excitation of the plate. The buckling load is determined from the measured natural frequencies and vibration mode shapes.