The invention provides an emulsion preparing system and an emulsion preparing method. The system comprises a preparing water tank and an automatic preparing instrument, wherein the automatic preparing instrument comprises an oil pump, an electromagnetic valve and a control box; the two ends of the oil pump are communicated with an emulsified oil supply device and the preparing water tank through pipes respectively for pumping the emulsified oil in the emulsified oil supply device into the preparing water tank; the two ends of the electromagnetic valve are communicated with a water supply device and the preparing water tank by pipes respectively for transferring the supplied water in the water supply device to the preparing water tank; the control box is connected with the oil pump and the electromagnetic valve respectively for controlling the added amount of the supplied water and the emulsified oil; and the preparing water tank is used for preparing the emulsion from the supplied water and the emulsified oil. When the emulsion preparing system and the emulsion preparing method, which are disclosed by the invention, are used, the labor intensity of workers is lowered, and high-efficiency, clean, safe and reliable high-pressure emulsion is provided for comprehensive working face hydraulic system equipment.