The invention discloses a combined-type current transformer testing device, and the device comprises a housing, a current meter, a power supply, three switch keys, two current meter pen jacks, three power positive jacks, and a power negative jack. One end of each switch key is electrically connected with a power output positive electrode, and the other ends of the three switch keys are respectively in electrical connection with three power positive jacks. The three power positive jacks are respectively provided with one positive testing line in an inserted manner. The power negative jack is electrically connected with a power output negative electrode. A negative testing line is inserted in the power negative jack. The current meter pen jacks are respectively in electrical connection with the current meter, and are respectively provided with one current meter pen in an inserted manner. The device combines the through-flow and polarity testing devices of a current transformer into one, and has functions of detecting the correctness of a secondary loop of the current transformer and judging the polarity of the current transformer.