A roughening tool for roughening a metallic surface of an inner wall of a pre-drilled workpiece bore is disclosed. The roughening tool has a profiled contour provided between the tool clamping shaft and the tool tip. With this contour, a roughened structure can be produced through rotation of the tool by processing the metallic surface in a material removing or non-material removing manner The roughening tool includes at least one profiled web which extends along the tool axis, protrudes from a main tool part, and on whose outer web back the profiled contour is provided.