The invention provides a multi-power-source automatic converting system, comprising at least one controller and an integration unit connected with at least one controller. The integration unit comprises an adapter, an electric operation mechanism and a circuit breaker, wherein the circuit breaker and the electric operation mechanism are mounted on a power supply automatic conversion device; the circuit breaker and the adapter are connected with a power supply wire; the adapter is connected with the circuit breaker, the electric operation mechanism and the controller simultaneously; and the electric operation mechanism is connected between the circuit breaker and the adapter. The multi-power-source automatic converting system provided by the invention uses a modulation design; and each module can be individually mounted, so that the multi-power-source automatic converting system is flexible and convenient to mount, and is applicable to the field and the large-size production with higher space arrangement requirement. Furthermore, the multi-power-source automatic converting system can be used for forming the integration units and the controller with different quantities to a power supply converting system with different functions, particularly a complex multi-power-source converting system, so that the defect that a PLC (Programmable Logic Controller) is difficult to develop, and the functions are flexible. Each integration unit is individual and has the advantages of convenience in maintenance and low maintenance cost.