In order to realize the reduction of gangue storage and emission reduction, the research on unit dense filling technology of paste material in shallow buried deep coal seam was carried out in Guojiawan Mine. Two sets of relatively independent mining system and filling system were designed, and three new preparation roadways were excavated. The mining was divided into three stages, and the method of ' mining one and leaving two ' was implemented. The mechanical model of the filling body was established, the strength requirement of the filling body was calculated, and the ratio of the material was obtained in the laboratory. The field application showed that the ground subsidence was small, the building was stable, and the load of the filling body was less than the design strength value. It was expected that the design of the whole unit dense filling area could consume 15 Mt tons of gangue and increase the sales revenue by 472 million yuan, which provided a reference for coal mining and gangue treatment under construction.