The invention relates to an alloy material and a preparation method thereof. The preparation method comprises the following steps: A, mixing the following components in parts by weight: 70-90 parts of a compatilizer and 10-30 parts of conductive filler; extruding and granulating to obtain a conductive master batch; B, mixing the following components in parts by weight: 70-90 part of polybutylene terephthalate and 10-30 parts of an anti-hydrolysis agent; extruding and granulating to obtain an anti-hydrolysis master batch; C, mixing the following components in parts by weight: 30-70 parts of polycarbonate, 30-70 parts of the polybutylene terephthalate, 5-15 parts of the conductive master batch and 2-10 parts of the anti-hydrolysis master batch; fusing and extruding; and in an extruding process, carrying out ultrasonic radiation treatment on a fused mixture to obtain a finished-product material. The alloy material prepared by the preparation method of the alloy material has very excellent conductivity and anti-impact performance.