Abstract: In order to solve the problem of long time, low efficiency, high cost and backward removal technology of fire dam in underground coal mine, based on the new type of physical blasting quickly dismantling underground fire dam technology, the drilling technology and blasting technology are researched. Combined with the characteristics of underground fire dam in coal mine, we propose the new technique that the blasting safety distance of fire dam is 10 m, the process cost of dismantling fire dam is controlled within 200 yuan, and the construction time is 15 min. The results show that the new type of physical blasting quickly dismantling underground fire dam technology can effectively ensure the safety of dismantling and improve the work efficiency of dismantling fire dam in underground coal mine.