Provided is a hydroxyethyl starch refining device. An ultrafiltration membrane assembly is utilized to separate ultrafiltration membranes of hydroxyethyl starch feed liquid, and a rejected water outlet of the ultrafiltration membrane assembly is connected with a feed liquid inlet of a frame filter through a pipeline. During the separation of the ultrafiltration membranes of the hydroxyethyl starch, excessive pressure of ultrafiltration membrane rejected water is utilized to enable the feed liquid to be micro-filtered through a precision filter. Therefore, the energy utilization rate is improved, and the quantity of microorganism of the feed liquid in the process of ultrafiltration membrane separation can be effectively controlled.