The invention discloses a brush device. The brush device comprises a fixed rod, a sliding cavity with a downward opening is fixedly formed in the fixed rod, a power cavity located in the fixed rod isformed at the right side of the sliding cavity, a transmission cavity located in the fixed rod is formed at the right side of the power cavity, a concave cavity with a rightward opening is formed in the right end face of the fixed rod, a sliding block is slidingly arranged in the sliding cavity, a threaded rod is arranged in the sliding block through threaded fit connection, the sliding block is arranged on the outer surface of the threaded rod through threaded fit connection and is in sliding fit connection with the upper end wall of the sliding cavity, and the threaded rod is in rotating fitconnection with the left end wall of the sliding cavity and rotatably penetrates through the right end wall of the sliding cavity to stretch into the power cavity. The brush device is simple in structure and convenient to use; motor-powered driving is adopted, flexible rotary cleaning is adopted, and the cleaning effect of the device is effectively improved.