The invention discloses a fiber access type electric energy meter with a function of harmonic detection, so as to accord with the communication standard of an intelligent transformer station. The energy meter mainly comprises (1) a data collection part: a fiber receiving and transmitting module receives a data message, sent by a communication unit, according with the standard, and transmits the data message to an Ethernet PHY controller, and the Ethernet PHY controller carries out frame verification of the received data, removes the frame head and tail and transmits the data to a DSP; (2), a data processing part: the DSP carries out the analysis of the data frame after the DSP receives a data package, obtains sampling data in the data frame, completes the calculation of voltage, current, harmonic waves at all orders and power through employing an FFT algorithm, transmits the sampling data to an MCU, and controls the power pulse output; (3), a data management part: the MCU completes the calculation and management of active electric energy, reactive electric energy and electricity demand; (4), a data communication part: a display module is used for display all data items, and an infrared or 485 communication interface is used for communication transmission and completes the monitoring of operation parameters.