The invention discloses a power system time synchronization optimization method based on time calibration and belongs to the field of power automation. The method is characterized by comprising the steps of S1001, calibrating an error of a self-time keeping signal; S1002, calibrating the error of a ground link signal; S1003, judging whether a satellite signal disappears or not; S1004, carrying outtime service through utilization of the satellite signal; S1005, calculating and eliminating deviation of the self-time keeping signal; S1006, judging whether the deviation exceeds a threshold or not; and S1007, sending out an alarm signal when a self-time keeping module loses efficacy. According to the power system time synchronization optimization method based on the time calibration, a deviation curve between the self-time keeping module and time service signal is obtained through utilization of a deviation curve obtaining method and under the condition that the satellite signal loses efficacy for a long time, the self-time keeping signal still can provide a high-precision time signal, so the reliable operation of a power system under the condition that the time service signal disappears for a long time is ensured.