The invention relates to a dosing device for liquids, with a replaceable distributor rail (1) and a plurality of dosing units (2) that are hydraulically connected to the distributor rail (1), wherein each dosing unit (2) has a valve unit (3), preferably provided with a suction valve, a discharge valve and a discharge cannula (7), and, detachably arranged on the valve unit (3), a piston-cylinder unit (8) for drawing in and measured discharging of the liquid, wherein each valve unit (3) has a hydraulic connection element for detachable hydraulic connection to the distributor rail (1), wherein the distributor rail (1) has an elongate fluid supply line, which has at its end side a supply connection (14) for the liquid and has dosing unit connections which are detachably coupled to the hydraulic connection elements of the dosing units (2).