The invention discloses a device and a method for nondestructively detecting materials for windings of power distribution transformers. The device comprises an acquisition sensor, a signal conditioning circuit, a signal acquisition card, a detection computer, a detection controller, a discharge circuit and a power module. The device and the method have the advantages that the materials for the windings of the power distribution transformers can be conveniently detected and nondestructively measured by power transformation operation and maintenance staffs, unlawful suppliers can be prevented from passing aluminum as copper, and accordingly the quality of network-connected power distribution transformer products can be guaranteed; the service lives of the power distribution transformers can be prolonged after the device and the method are applied, the stability of the power distribution transformers can be improved, and accordingly the device and the method can be further comprehensively popularized to cover admission detection work on power distribution transformers of power distribution network systems of the state grid corporation and have obvious direct and indirect benefits; the work efficiency of the power transformation operation and maintenance staffs can be effectively improved, and the management level of the power transformation operation and maintenance staffs can be upgraded; problems can be discovered early, accordingly, the power supply reliability can be improved, safe and reliable operation of power grids can be fundamentally guaranteed, and the device and the method have obvious economic benefits.