The invention discloses a control device of a current-limiting protection system for a current transformer, and the current-limiting control method thereof. The control device provided by the invention comprises a PWM (pulse-width modulation) inverter, a correction reactor, an inversion output transformer, an output filter, an AC signal sampling circuit, a DC signal sampling circuit and a processor. Compared with other operation protecting products for a current transformer, the device provided by the invention has the advantages that effective current-limiting protection can be achieved during the running process of the current transformer, the respond is fast, and high-current impact during the running process in case of instant and long-time short circuits and the like can be resisted; the method provided by the invention has high reliability, that the current transformer can maintain limited current output during failure period can be effectively ensured, the current transformer can be effectively protected, and meanwhile, better voltage current waveform output can be obtained, and the power supply sustainability can be maintained.