The invention discloses a low-power-dissipation power supply circuit. The circuit comprises a biasing sub-circuit for providing a biasing voltage, a current source sub-circuit which is connected with the biasing sub-circuit and is used in mirror current, an amplifying sub-circuit connected with the current source sub-circuit, a current mirror sub-circuit connected with the amplifying sub-circuit, and a feedback sub-circuit and compensating capacitor connected with the amplifying sub-circuit and the current mirror sub-circuit, wherein the current source sub-circuit provides work current for the low-power-dissipation power supply circuit, and the amplifying sub-circuit compares an output voltage of the feedback sub-circuit with a reference voltage of a reference voltage end and amplifies a comparison result to respond to the change of load current. In the low-power-dissipation power supply circuit, the circuit structure is stable, the change of the load current can be quickly responded to, and the nanoampere level of static power dissipation is achieved.