An annular silicon steel sheet having a separable structure, a plurality of tooth protrusions are arranged radially inward on an inner side of a circular ring and are distributed at equal intervals, the annular silicon steel sheet includes a circular-ring-like-shaped silicon steel sheet body and a separation part, and a wedge-shaped gap matched with the shape of the separation part is arranged on the silicon steel sheet body, and can be matched with the separation part to form a complete annular silicon steel sheet; and the separation part is provided with locking parts on contact surfaces with the silicon steel sheet body at two sides, so that the separation part is not easy to get loose after being combined with the silicon steel sheet body. The annular silicon steel sheet capable of being freely separated and combined enables difficulty of an installation process to drop, thus a requirement for the degree of matching precision of sizes of the silicon steel sheet and an installing housing can be reduced, and production cost of the silicon steel sheet can be reduced.