Abstract: The direct alloying process of manganese ore was carried out by the process of double slag dephosphorization and less slag smelting. The samples of end-point slag and molten steel were selected for chemical composition and mineral phase detection, and the influence of the optimum ratio of different manganese ores and slag-making materials on the manganese distribution ratio between slag and steel was analyzed. The results show that the manganese yield is 15.87 %-79.3 %, with an average of 45.05 %. The manganese distribution ratio between slag and steel is 21.97-37.96, with an average of 31.17. The dephosphorization rate is 86 %-92 %, with an average of 88 %. The manganese distribution between slag and steel obtained by the charge ratio of group 9, group 4 and group 13 is relatively low, between 22-25. The main factors affecting the distribution ratio of manganese between slag and steel are molten steel temperature, end point carbon content, slag basicity and iron oxide. The quantitative relationship between these factors and the distribution ratio of manganese between slag and steel was obtained.The charge ratio of the low manganese distribution ratio is that the 
proportion of lime is 25 %-30 %, the proportion of sinter is 30 %-40 %, the proportion of manganese ore is 15 %-20 %, and the proportion of light burnt dolomite is 20 %-30 %. 

Key words: direct alloying of manganese ore, converter charge ratio, mineral phase composition of slag, manganese distribution ratio between slag and molten steel