Plastic-case circuit breaker is one of the important switching equipment in low-voltage distribution network, which can automatically cut off the power grid after the current exceeds the trip setting, and protect the distribution network and industrial equipment from damage. The traditional low-voltage circuit breaker uses a thermomagnetic or electronic controller, and the thermomagnetic structure relies on the thermal effect and magnetic effect of electricity to complete the tripping action, and there is no data interaction ability and intelligent control needs, which can not meet the requirements of the comprehensive development of the power energy network to transform into a digital, networked, intelligent new power system. In order to meet the requirements of reliability, safety and intelligence of plastic-case circuit breaker for new power system, an intelligent plastic-case circuit breaker device for distribution network is proposed. The intelligent device has the main line power supply, combined with the backup battery auxiliary power supply mode, with strong and weak electricity independent characteristics, support high-precision voltage and current acquisition capabilities, with HPLC/RS485 uplink communication mode, Bluetooth local communication interface and special expansion interface, can adapt to various external devices according to the application scenario. The software supports remote communication, telemetry, remote control, self-diagnosis, fault analysis, meter transcription data verification and other capabilities, and has multiple harmonics and other power quality parameter detection capabilities. The intelligent monitoring and remote control functions of intelligent plastic-case circuit breaker are realized, which effectively improves the digital and intelligent characteristics of intelligent plastic-case circuit breaker. The device has been tested by the third party testing institution and has high voltage and current acquisition accuracy and running stability.