An interlocking structure of a power conversion system is provided. A first power circuit group is connected to a first power source and includes a first and a fourth switch. A second power circuit group is connected to a second power source and includes a second and a fifth switch. A limiting mechanism includes a first limiting portion, a second limiting portion, a fourth limiting portion, a fifth limiting portion, a first accommodating portion, and a second accommodating portion. The first switch is switched off to disconnect the first power source. Then, a limiting structure is moved to connect the second power source. Accordingly, the first power source is disconnected, and the second power source is connected, allowing repair or maintenance of the first power source to be performed without interrupting the supply of power from the power conversion system.