Abstract: Fine-grained low-grade manganese ore is difficult to extract due to some mineral processing technology problems, such as non-selective aggregation between ore particles, large dosage of flotation reagents, and low efficiency of flotation. In recent years, multiple types of collectors have been used for the flotation of low grade manganese ore (less than 13%), while the concentrate grade was between 16.9% and 18.3%, and the recovery between 56% and 97%. Although the recovery is ideal, the concentrate grade is too low. RA-92 was selected as a new collector in the flotation of low grade manganese carbonate (grade of 10.7%) ores from Fenghuang-Huayuan area in Hunan in this study. The effects of the grinding fineness, pH, inhibitors, and the collecting agent dosage were investigated and the optimum conditions were obtained. The concentrate grade ranges from 10.7% of the original ores to 17.4% in concentrate, and recovery reached 80.2%. This indicates that the new collector has better selectivity and a stronger ability for collecting manganese carbonate. The collector RA-92 is a good prospect in low grade manganese carbonate due to the relatively simple flotation process, less dosage of collector and lower flotation costs.