Abstract: In view of the problems of conventional collector, such as high flotation temperature and high energy consumption, we developed a new collector DX-1 for anionic reverse flotation at normal temperature. In order to verify the flotation effect of the agent on the actual mineral, the reverse flotation test was carried out on the mixed magnetite concentrate of 40.05% of the iron ore grade. The test results show that the new collector can be adapted to 20 degree low temperature environment. When pH=11.5 is applied, the iron concentrate with grade 65.23% and recovery rate of 83.55% can be obtained through 1 coarse 1 fine 3 scanning closed circuit test processes. The final product of SEM and EDS analysis results showed that: DX-1 of quartz, dolomite and other gangue mineral collector has good selectivity; coarse particles in the products is not completely monomer dissociation is the main reason to further improve the effect of concentrate, and tailings of fine iron minerals containing micro bubble entrainment phenomenon, affect the metal recovery rate.