The invention provides a multi-speed telemetering time synchronizing method which achieves time synchronization of three peripheral devices. The three peripheral devices comprise a device A, a device B and a device C, wherein the device A is only controlled by a system in an electric reset mode; the device B is controlled by the system in an electric reset and CPU software reset mode; the device C is controlled by the system in an electric reset and CPU software reset mode and needs speed regulation. The method comprises the steps that (1) interrupt intervals of the three devices are structured; (2) electric time interrupt of the three devices is synchronized; (3) when CUP software reset is conducted on the device B and the device C, the release time of CPU software reset of the device B and the device C is controlled so that interrupt can be synchronized again; (4) when speed switching is conducted on the device C, interrupt synchronization is kept through three-level speed synchronization. The multi-speed telemetering time synchronizing method resolves the problems of interrupt source synchronization of the peripheral devices.