Abstract: A major breakthrough for high quality manganese ore prospecting was made in Maerkansu area, west Kunlun. The manganese ore belt in Maerkansu area is stable with large thickness and rich grade, and the manganese deposits belong to a typical marine sedimentary manganese deposit. In this paper, we study the geological background of mineralization, the geological characteristics of typical deposits and ore-controlling geological conditions. The ore-prospecting criterias were proposed, which include the Carbonaceous micrite, anticline structure, fracture structure, remote sensing and geophysics. It is indicated that there is huge prospecting potential of Maerkansu manganese ore belt. Prospecting work should be reinforced in the south wing of Aoertuokane deposit, Suesalburak, Botuoyan and Tuokuzibulake, and so on. Meanwhile, more attentions should be paid to the study of ore field structure to develop ore prospecting in depth. Prospecting work of Carboniferous manganese deposits in the western and northen margin of Tarim needs further attentions.