The invention relates to a low-voltage circuit breaker, and particularly to an Internet of Things based intelligent modular low-voltage circuit breaker and an operating method therefor. The intelligent modular low-voltage circuit breaker comprises a circuit breaker shell, wherein a power supply module, a sensor module, an electromagnetic control mechanism, a contact system and an embedded type control chip are arranged in the circuit breaker shell; and the power supply module is connected with the sensor module and the embedded type control chip separately. According to the Internet of Things based intelligent modular low-voltage circuit breaker and the operating method therefor, the intelligent modular low-voltage circuit breaker is compact in structure, capable of realizing remote automatic control, and capable of improving the operation precision.