The invention relates to a time synchronizer of electric power, and especially to a Beidou GPS dual-mode electric power time synchronizer. The synchronizer comprises a Beidou satellite reception module, a GPS satellite reception module, an input module, a time service module, a display and control module, an output module, a power supply module, and a common base plate. The time service module is used for receiving time and state information from the Beidou satellite reception module and the GPS satellite reception module or an external input clock source from the input module, generating and maintaining local time information, and outputting the time information and alarming information in a serial data information format and a pulse mode to the output module. The Beidou GPS dual-mode electric power time synchronizer replaces an original electric power GPS satellite clock, provides a dual backup receiver based on Beidou compatible GPS for users, satisfies the user demands during the electric power system time service, has the characteristics of high accuracy and stable performance, and meets the user demands during the electric power system time service.