The invention discloses a multi-equipment scanning method based on RS485 bus communication and a power electronic system. The multi-equipment scanning method comprises the following steps that: S1, a host is powered on, and starts to scan slave equipment; S2, the host turns on the power supply of first-stage slave equipment (N=1); S3, the host sends a scanning command to Nth-stage slave equipment through an RS485 connection link; S4, the Nth-stage slave equipment makes a scanning response to the scanning request of the host; and S5, the host judges whether or not the scanning response of the Nth-stage slave equipment is received: when the host receives the scanning response, the host processes scanning data, instructs the Nth-stage slave equipment to turn on the power supply of (N+1)th-stage slave equipment, sets N=N+1, and returns to step 3; an when the host does not receive the scanning response, the host ends scanning and feeds back a scanning result. Identification scanning can be performed when the quantity of slave equipment communication addresses is unknown, so that data conflict caused by RS485 multi-equipment scanning is avoided.