To effectively supply coolant to a cutting portion, while facilitating a manufacturing.

A cut-out shaped pocket 2a is formed from a tip to one side at a tip part of a tool main body 2. A throw-away tip 3 forming a cutting edge 3a is attachably/detachably fitted on a tip mounting seat 2b within the pocket 2a. In the tool main body 2, an internal supply passage 4a is formed along the axis O1 from a base end side up to the vicinity of the tip part, a nozzle 4b having a smaller diameter than that of the internal supply passage 4a is formed to be communicated with the internal supply passage 4a from the pocket 2a of the tool main body 2. By these, a coolant supply passage 4 leading from the base end side of the tool main body 2 to an outside face of the tip part is formed. In the tool main body 2, the nozzle 4b to be the vicinity of an opening part 4c on the outside face side of the coolant supply passage 4 is provided in a direction in which the axis O2 crosses a straight line L passing a center of the opening part 4c and the cutting edge 3a. In the nozzle 4b a subsidiary flow passage 5 is provided toward the cutting edge 3a from a position on the axis O2 direction inward side of the nozzle 4b instead of the opening part 4c.