The invention discloses a current transformer interface testing device and method. The device comprises a PLC, an industrial control computer, an analog input interface, an analog output interface, a digital input interface, a digital output interface and a communication interface. The PLC is connected with corresponding interfaces of an external current transformer respectively through the analog input interface, the analog output interface, the digital input interface and the digital output interface. The PLC is connected with the industrial control computer. The industrial control computer is connected with the current transformer through the communication interface or the PLC is connected with the current transformer through the communication interface. According to the invention, the industrial control computer is utilized, after combined with the PLC, the industrial control computer has the high-speed operation capability, standardized modules and the strong expansion capability, and various interfaces of the current transformer are rapidly tested by means of software logic control; in addition, the mobile structure is used, so that the device can effectively, rapidly and flexibly complete the interface testing work in all directions.