The invention relates to a regulating valve, which is attachable, in particular in a bore of a hydraulic door closer, executed with a female thread. The regulating valve has a body, adjoined by a regulating area, and a thread provided with an anti-rotation means. The thread with the anti-rotation element can be screwed into the female thread of the bore of the hydraulic door closer. In order to provide a regulating valve with a simple design while excluding unwanted adjustment of the regulating valve during the operation, the anti-rotation means includes a raised area, which can cooperate with the bore or the female thread of the door closer.