The invention discloses a communication module for general use of public and private networks of an electricity system and its communication method. In the communication module, a main control chip iselectrically connected with an Ethernet interface, an UART interface, an USIM interface, an USB interface, a control interface, a power management chip, a radio frequency transceiving chip; the radiofrequency transceiving chip is connected to a radio frequency front end. The module can realize the self-adaptive switching function of public and private networks through a set of chip. The communication module has variable interfaces, supports antenna branch receiving and data business, provides rich user signal interfaces and supports a standard AT command set. Moreover, the product is small and flexible in structure, and convenient to mount and repair; through different cable supporting gateways, serial ports, and USB interfaces, multiple application scenes and businesses can be adapted.A minitype intelligent terminal can be widely applicable to multiple electrical businesses like power distribution automation, fault indicator, video monitoring, mobile tour inspection, mobile working.