A simulation current signal generation circuit applied to a power conversion circuit is disclosed. The power conversion circuit has an output terminal and includes an output stage, a PWM circuit and an impedance component. One terminal of impedance component is coupled to the output terminal. The generation circuit includes a first current signal circuit, a second current signal circuit and a switching circuit. The first current signal circuit, coupled to another terminal of impedance component, provides a first current signal. The second current signal circuit, coupled to the output stage, senses a current of a power switch in the output stage to provide a second current signal. The switching circuit, coupled to the first current signal circuit, second current signal circuit and PWM circuit respectively, selectively outputs the first current signal or second current signal according to a PWM signal provided by the PWM circuit.