Shaking table separation, the main method in dealing with antimony oxide tailings, has too many defects such as poor operational stability and low recovery. A new technical idea was proposed to solve these problems by using an agitated Reflux Classifier to pre-concentrate the tailings before they went to shaking tables. The principle of this separating system was based on hindered settling and agitation effect. This study focuses on the regulation of the bed density distribution in the agitated Reflux Classifier by mechanical agitation to influence particle separation. The experimental results showed that 73.13% of feed are discarded in the tailings by the agitated Reflux Classifier. At the same time, suitable mechanical agitation was able to improve particle properties (both in Sb grade and particle size), which is beneficial to the subsequent shaking table process. Hence this technology has clear potential for pretreating the antimony oxide tailings. (C) 2020 Published by Elsevier B.V.