Abstract: With the continuous improvements of the mine environmental protection of China, the research and development of green beneficiation reagents are particularly important. Starch is wide Source, cheap, green, renewable, and easy degradable. It is often used as a depressant for sulfide minerals such as pyrite, galena, molybdenite and silicates such as hornblende, talc, serpentine, etc. This paper mainly introduces the structures and properties of starch, and expounds the role of starch in flotation of sulfide minerals and gangue minerals. In addition, the depression mechanisms are revealed. The paper provides the references for the scholars to carry out the in-depth research on starch and realize the wide application of starch in mineral processing fields.>