The invention relates to a detection method, a micro-electromechanical component and a micro-detection structure of a micro-mechanical structure, suitable for obtaining the mechanical properties of a film layer used by the micro-mechanical structure. The detection method comprises the following steps: firstly, the micro-detection structure is formed on a basal material of the micro-detection structure, wherein a part to be detected on the micro-detection structure is made of the film layer; then, the part to be detected is vibrated, and the resonant frequency of the part to be detected is measured; and the mechanical properties of the part to be detected are derived from the physical dimensions, the density and the resonant frequency of the part to be detected so as to obtain the mechanical properties of the film layer. In addition, the modes of the micro-detection structure comprise a micro-cantilever beam and a borderless beam. The invention is additionally provided with a piling layer on the surface of a structure layer so as to improve the measurement accuracy of the resonant frequency of a cantilever beam and more accurately obtain the mechanical properties of the cantilever beam, i.e. the mechanical properties of the film layer. Furthermore, the prior straight supporting beam is replaced by a flexible structure, such as a folding beam so as to more accurately obtain the mechanical properties of the beam, i.e. the mechanical properties of the film layer.