Disclosed is a low power consumption switching circuit with voltage isolation function for a PMOS transistor bulk, including a bulk voltage switching control unit, a bulk voltage switching unit, a first voltage input terminal, a second voltage input terminal, and a bulk voltage output terminal. The bulk voltage switching control unit includes a plurality of PMOS transistors and weak pull-down devices, and is configured to generate a control signal to control the bulk voltage switching unit to make the bulk voltage output terminal to be connected to a higher potential between the first voltage input terminal and the second voltage input terminal. The bulk voltage switching unit includes a plurality of PMOS transistors, and is configured to connect bulks of the PMOS transistors to the higher potential between the first voltage input terminal and the second voltage input terminal. Each of the PMOS transistors is a low-withstand-voltage device.