Accurate quantitative fertilization device

The utility model discloses an accurate quantitative fertilizing device which comprises a water pump, a water and fertilizer dissolving barrel, an expandable elastic water bag, a fertilizing handheld pipe and a quantitative control assembly, a water inlet of the water pump is connected with a water inlet pipe; a water inlet end of the water inlet pipe extends into the water-fertilizer dissolving barrel; a water outlet of the water pump is communicated with a liquid inlet of the expandable elastic water bag through a liquid inlet pipe, and a liquid outlet of the expandable elastic water bag is connected with a liquid outlet pipe; the liquid outlet pipe is connected with a fertilization handheld pipe through a fertilization hose; the quantitative control assembly comprises a flow quantitative control instrument, a pressure gauge, a one-way valve, a flow meter and an electromagnetic valve, the pressure gauge and the one-way valve are installed on the liquid inlet pipe, and the flow meter and the electromagnetic