A multifunctional transformer comprehensive testing device is mainly composed of a working power supply, a data acquisition system, a CPU system, an operation interface, a power output control system, a relay system and a binding post. The data acquisition system comprises a load acquisition system, an impedance acquisition system and a direct resistance acquisition system. The multifunctional transformer comprehensive testing device is characterized in that a demagnetization acquisition system is further arranged in the data acquisition system, the demagnetization acquisition system is connected with the CPU system through a serial port, the demagnetization acquisition system comprises three AD conversion chips, and each AD conversion chip is provided with an AD7705 analog-digital converter, a serial input / output isolation circuit, a power isolation circuit, a crystal oscillating circuit, a reference voltage source circuit and an analog signal input circuit. According to the multifunctional transformer comprehensive testing device, since the demagnetization acquisition system is additionally arranged, four transformer winding testing devices are used in a combined mode, the occupied space and the frequency of mounting and dismounting transformers by detection personnel are reduced, personal safety is ensured, residual magnetism in the transformers is eliminated rapidly, and work efficiency is improved.