Multifunctional electric power meter, a multifunctional intelligent electric power meter with programmable measurement, display, RS485 digital communication and electric energy pulse output, can complete three-phase electric parameter measurement (three-phase voltage, three-phase current, active power, reactive power, apparent power, power factor, frequency, etc.), harmonic measurement, power grid quality analysis (voltage crest factor, current K factor, telephone waveform factor, voltage and current unbalance, voltage and current sequence quantity, etc.), four-quadrant electric energy metering, multi-rate electric energy metering, maximum demand recording, SOE event recording, data display, collection and transmission, and can be widely used in substation automation, distribution automation, intelligent buildings, and internal electric energy measurement, management, and assessment of enterprises. The measurement accuracy is 0.5 level, and LCD field display and remote RS-485 digital interface communication are realized, and the standard DL/T 645-2007 or MODBUS-RTU communication protocol is adopted.