The invention discloses a time-varying baseband multipath channel analog device and device based on an FPGA (Field-Programmable Gate Array) and mainly solves the problem that in the prior art, a hardware platform is difficult to establish due to the fact that a channel model mathematical expression form is not concise enough, the required operation quantity is still very high and a channel analog device is high in hardware realization complexity and complex in structure. The device comprises a signal input module, a Rayleigh channel generation module, a multipath overlapping module and a channel output module. The method comprises the steps of (1), obtaining input signals; (2), generating Rayleigh channel output signals; (3), storing multipath parameters; (4), setting the number of Rayleigh channels; (5), obtaining prolonged time delay signals; (6), obtaining multipath total fading signals; and (7), obtaining output signals. The device and the method have the advantages of a simple structure, few hardware realization resources and configurable multipath parameters and are applicable to practical use of various wireless communication systems.