The utility model provides a liquid manure supply metering device, includes the base, install the engine above the base and set up the force (forcing) pump support, installation force (forcing) pump above the force (forcing) pump support, force (forcing) pump are equipped with the belt pulley, the engine is connected with belt for the force (forcing) pump, force (forcing) pump upper portion is equipped with overhead tank, manometer and air -vent valve, the lower part of force (forcing) pump is equipped with the feed pipe, and upper portion is equipped with two high -voltage tubes, be equipped with filter screen and overflow pipe on the feed pipe, overflow pipe and air -vent valve intercommunication, the high -voltage tube is connected on the outlet pipe, be equipped with fluidflowmeter on the outlet pipe. Beneficial effect: but adopting the liquid manure supply metering device and adjust pressure valve of measurable, can accomplishing according to crops required moisture in different growth periods and fertilizer volume, come the fertilizer application operation that drips irrigation of quantitative moisturizing and quantitative supplementary fertilizer, adopt drip irrigation zone pressure requirement under the membrane of the different demands of adjustment pressure adaptation, the supply of assurance liquid manure is even, satisfies agricultural crop growth demand.