The present disclosure relates to a rotary burs with variable pitch. The file is made up of a cutter head (1) and a cutter handle (2). The cutter head is connected with the cutter handle. Multiple groups of cutter teeth are distributed on the cutter head. Each group of cutter teeth can be mixed cutter teeth, and can also be a single cutter tooth. The mixed cutter teeth are respectively a group of cutter teeth composed of a large tooth (3), a medium tooth (4) and a fine tooth (5) sequentially arranged, and can also be a group of mixed cutter teeth formed by combining any two of a large tooth, a medium tooth and a fine tooth.