The invention discloses an intelligent monitoring unit for vehicle-mounted three-phase alternating current power supply equipment. The intelligent monitoring unit comprises a power mother board and a control panel, wherein the power mother board comprises an auxiliary power supply unit, a lightning protection unit and a protection action executing unit; the control panel comprises a three-phase alternating current detecting unit, a three-phase alternating voltage detecting unit, an electric leakage detecting unit, a main control unit and a ground state detecting unit, wherein the ground state detecting unit adopts dual-ground detection, the control panel integrates a CAN (Controller Area Network) bus communication function and a 485 serial bus communication function. The whole intelligent monitoring unit has multiple functions of lightning protection, three-phase alternating current overcurrent, short circuit, electric leakage protection, three-phase alternating voltage overvoltage, undervoltage protection, ground state detection protection and the like, and provides a safer driving environment for a vehicle driving operator.