The present disclosure discloses a dynamic equivalent circuit of a combined heat and power system, and a working method thereof. Controlled sources are used to represent a thermoelectric coupling source; equivalent inductance is used to represent a delay of a heat transmission pipeline; equivalent resistance is used to represent a heat load and a heat loss of the heat transmission pipeline; and equivalent capacitance is used to represent a heat storage water tank. A circuit model is used to uniformly represent two thermoelectric heterogeneous energy sources, and a single power simulation tool may be used to simulate a combined heat and power system, so that the simulation system has a simple structure and is easy to develop and maintain.