A liquid preparation tank for accelerating substance dissolution comprises a liquid adding port, a flow guide groove, a flow guide partition plate, a flow guide pipe, a circulating pump, a water inletpipe, a liquid preparation tank body, a sampling port, a water inlet valve, a circulating valve, a circulating pipe and a liquid separator. The diversion trench is arranged at the bottom of the liquid preparation tank, and the liquid adding port is connected with the liquid separator; an outlet of the circulating pump is connected with an inlet of the liquid distributor through a pipeline, and the water inlet pipe is connected with a tee joint through a valve. The flow guide groove is composed of a plurality of flow guide partition plates and four flow guide pipes, the flow guide pipes are connected with the liquid adding port, and the sampling port is located above the liquid preparation tank. According to the utility model, the flow guide groove is formed in the lower part of the liquidpreparation tank, and the four opposite flow guide pipes and arc-shaped flow guide partition plates are used for enabling a solvent to enter the liquid preparation tank and flow along the flow guidepartition plates to form rotational flow, so that solute and the solvent are in full contact, and the purpose of accelerating substance dissolution is achieved; and a circulating pump and a circulating pipe are additionally arranged outside the liquid preparation tank, so that the solution is mixed more uniformly.