Sanitary mixing valve having a) a housing which has an inlet for cold water, an inlet for hot water, and an outlet for mixed water; b) a first control disc which is disposed so as to be stationary in the housing and which has a passage opening for cold water, a passage opening for hot water, and a passage opening for mixed water; c) a second control disc which bears so as to be displaceable on the first control disc and which has one passage opening which more or less overlaps the passage openings (9, 10) of the first control disc, depending on the relative position of the two control discs (8, 14); d) an entrainment part which is connected to the second control disc in a movement-linked manner; e) an actuating stem which is pivotably mounted in a guide part which is rotatably mounted in the housing, and which at one end is connected to the entrainment part in a movement-linked manner; wherein f) the entrainment part has a depression which jointly with the passage opening of the second control disc forms a diversion duct for the water to be mixed and comprises a noise-damping installation in the form of a plurality of ribs which extend away from the base of the depression into the passage opening of the second control disc; characterized in that g) the passage opening of the second control disc, when viewed from the stationary control disc, has a key-hole shape having a comparatively wide region and comparatively narrow region; h) the comparatively wide region more or less overlaps the passage openings for cold and hot water of the first control disc, depending on the relative position of the two control discs (8, 14); i) the comparatively narrow region overlaps the passage opening for mixed water of the first control disc; k) the ribs of the entrainment part extend substantially across the entire depression, and at those ends that are adjacent to the comparatively wide region of the passage opening of the second control disc have a larger mutual spacing than at the opposite ends. a) a housing which has an inlet for cold water, an inlet for hot water, and an outlet for mixed water; b) a first control disc which is disposed so as to be stationary in the housing and which has a passage opening for cold water, a passage opening for hot water, and a passage opening for mixed water; c) a second control disc which bears so as to be displaceable on the first control disc and which has one passage opening which more or less overlaps the passage openings (9, 10) of the first control disc, depending on the relative position of the two control discs (8, 14); d) an entrainment part which is connected to the second control disc in a movement-linked manner; e) an actuating stem which is pivotably mounted in a guide part which is rotatably mounted in the housing, and which at one end is connected to the entrainment part in a movement-linked manner; wherein f) the entrainment part has a depression which jointly with the passage opening of the second control disc forms a diversion duct for the water to be mixed and comprises a noise-damping installation in the form of a plurality of ribs which extend away from the base of the depression into the passage opening of the second control disc; characterized in that g) the passage opening of the second control disc, when viewed from the stationary control disc, has a key-hole shape having a comparatively wide region and comparatively narrow region; h) the comparatively wide region more or less overlaps the passage openings for cold and hot water of the first control disc, depending on the relative position of the two control discs (8, 14); i) the comparatively narrow region overlaps the passage opening for mixed water of the first control disc; k) the ribs of the entrainment part extend substantially across the entire depression, and at those ends that are adjacent to the comparatively wide region of the passage opening of the second control disc have a larger mutual spacing than at the opposite ends.