The metering color masterbatch mixer can automatically mix 1 kind of plastic raw material and 1-4 kinds of color masterbatch or additives according to proportion, which is suitable for injection molding, extrusion or blow molding production. This series of products adopts hybrid stepper motor and special microcomputer controller, which can accurately measure the proportion of color masterbatch and additives. The mixer can be connected with all kinds of molding machine signals and run synchronously to ensure the consistency of the forming product performance.