Abstract: Zhonggu ore field is one of important ore concentration areas in Nanjing-Wuhu region.Based on the previous work and research，through the analysis of the geological background of ore formation and geological characteristics of various types of deposits，the paper summarizes the ore formation laws such as “three floor three types in five modes” and fenster -channel -grouping -complementation -three-storied building”，and the ore prospecting indicators including rich alkaline rich iron，high oxidation and low magnesium magmatic rock，calcium-containing shale，limestone of Trias and gypsolyte stratum and gravity- magnetic abnormal combination，which are of certain reference and guidance significance to the new round of iron ore exploration.

Key words: Zhonggu ore field, Ore formation mode, Ore hosting structure, Ore formation law