To provide a working brush capable of preventing the occurrence of a core shift during the rotation of the brush even if the brush is frequently replaced.

The working brush 1 is formed by fixing a brush unit 5 including concentrically connected channel brushes 4, to a fixed surface 2b of a base unit 2 including a rotating shaft 2a and the fixed surface 2b, by a fixing member 3a and a male screw 3b. A long-sized channel brush 4 with a brush piece 4a clamped by a core wire 4b and a strip body 4c is formed in circular shape to form the channel brush 4, and then four parts of the strip body 4c are welded for connection to form the brush unit 5.