Abstract: A dust collecting attachment includes a dust suction portion and a main body. The main body has a dust collection passage communicated with the dust suction portion. The dust suction portion has a negative pressure by exerting a suction force to the dust collection passage from a hose. The dust suction portion includes an inner pipe through which a tip tool passes, a first dust suction flow passage, and a second dust suction flow passage. The first dust suction flow passage opens a first suction opening to a side of a workpiece in an outside in a radial direction of the inner pipe and is communicated with the dust collection passage. The second dust suction flow passage opens a second suction opening to an opposite side of the workpiece in the outside in the radial direction of the inner pipe and is communicated with the dust collection passage.