The invention discloses an aluminum tape wrapping device and its operation method. The device comprises a fixed jaw and a moveable jaw. Both of the jaws are symmetrically arranged on the device body. The inner side of the fixed jaw is provided with an arc surface which cooperates with the shape of the wire outer surface. The upper end of the fixed jaw is provided with a flexible notch. One end of the flexible notch is fixedly arranged on the fixed jaw while the other end of the flexible notch is provided with an aluminum tape clamping notch. Through the arrangement of the arc surface with the shape of the wire outer surface and at the inner side of the fixed jaw and the arrangement of the flexible notch, the nut can be rotated and adjusted so that the flexible notch can rotate within zero to fifteen degrees. During the process of aluminum tape wrapping, the fixed jaw presses the aluminum tape tightly onto the outer surface of the wire. In this way, the loosened wrapping of aluminum tape can be avoided. According to the operation method of the aluminum tape wrapping device, it is possible to calculate the length L required by the aluminum tape according to the clamp width so that the cut length of the aluminum tape can be controlled, therefore, avoiding waste of aluminum tape caused for its excessive cut length. The method is simple to operate and adopts a uniform technology.