Abstract: With rapid development and application of large sized coal mining equipment,the superfine particles minus 200 μm in raw coal increase day by day that causes not only wasting of coal resource but also severe environmental pollution.The performance of using anionic or non ionic polyacrylamide as flocculant to clarify coal washing water containing a lot of difficult flocculable fine particles is not ideal because there is a high electric potential on the surface of particles.A synthesized cationic flocculant PQAAM is therefore developed and has been tested in lab.The results of test are excellent.