The invention discloses a frequency dispersion curve solving method and device for a multi-medium model. The method comprises the following steps: automatically judging a medium model according to input model data, and selecting corresponding vibration modes; under a theoretical framework of a generalized anti-transmission coefficient method, constructing a duration function family of the vibration modes; searching all vibration modes in the medium model based on the duration function family, connecting the vibration modes with the same order, and drawing a frequency dispersion curve. According to the method provided by the invention, various different medium models can be flexibly processed, and surface wave frequency dispersion curves required by users can be stably, quickly, and precisely calculated, so that the method is universally applied; The invention differs from the prior art in the method, adaptable medium models (5 medium models and plate conditions are additionally included), medium particularity, and solvable vibration mode types (Rayleigh waves, Love waves, and sound waves), and any combination of the three aspects is within the protection range of the invention.