The invention discloses a simple and accurate water metering device, and relates to the technical field of water metering devices. The simple and accurate water metering device comprises a frame body,a liquid storage tank and a water pump, wherein the liquid storage tank and the water pump are arranged inside the frame body, the water pump is located on one side of the liquid storage tank, the water pump is connected with the liquid storage tank through a first conveying pipe, and the side, close to the water pump, of the first conveying pipe is provided with a flow meter. According to the device, one solenoid valve and a weighting sensor of a container are omitted, so that the overall structure of the device is simple, pipelines are reduced, installation is facilitated, the installationefficiency of the device is greatly improved, and the cost is reduced at the same time; in addition, metering is carried out only through the flow meter, the weighing sensor is not needed, so that theflow meter can accurately measure, and the metering precision of the device can be conveniently improved; and meanwhile, a control circuit does not need the weighing sensor, so that fault points arereduced, and the reliability of the whole system is greatly improved.