Abstract: According to the characteristics of high concentration and long lasting of duct after blasting or at ore-drawing of chamber in underground metal mine，and through analyzing the reasons for the defect and deficiency of the existing dust suppression by spraying，it is proposed that high-pressure dust suppression spray is used to directly spray water on the dust，which can reduce the dust concentration after blasting or at ore-drawing from the beginning.According to this idea，the dust suppression spray is designed for underground metal mines.The dustfall spray can be controlled by the dust concentration sensor to realize automation of the dust removal process.At present，this technique has been applied in Huibaoling Iron Mine，and shortened 60% of time on fume after blasting，reduced dust concentration above 75% in mine roadway，and lowered the dust concentration above 60% in upper level of the air return roadway.

Key words: Underground mine, Dust, High pressure water gun, Direct dust fall