In order to overcvome the shortage of current dust control technology in coal mine, especially the traditional water spray method, a two-phase foam materials preparation experimental system was established based on the simulation of water and air conditions in underground coal mine. And a new technique which can prepare high-performance foam was proposed, and the main technical parameters and application conditions to implement foam dedusting were determined through plenty of experimental. Then, the new technique had been applied in two large underground coal mine. The results show that its dedusting efficiency to total dust and respirable dust reached 90.5% and 85.4% in the fully-mechanized excavated face, as 1.97 times and 1.88 times higher than water spray respectively. However, its water consumption is only as 10% to 20% as conventional water spray. It is proved that this new technique for preparation of foam can reduce mine dust concentration remarkably and improved the working environment obviously, and has a broad application prospect and promotion value to control dust in underground coal mines and other related industry.