Abstract: Automatic control of coal separation is for the purpose of improving productivity, while product quality must be ensured. There are many parameters that will affect the separation in the procedure of separation,among which, some must be stabilized in a optimum range and some are correlative that needs a optimum match. Human observation and manual operation can hardly meet it. Therefore automatic control is of great significance. The paper focuses on the current status and effects obtained in automatic control technique research for coal preparations in our country.