Abstract: The analysis on the geochemical composition of various types of ore-bearing skarn showed that the fluid containing Ti，Fe，Mn，Mg and Ca are transferring and exchanging among biotite granites and skarn rocks in Nanshan mining area，forming skarn minerals.The ore-bearing skarn and marble have similar REE patterns in right-inclined type，and enrich in LREE with Eu in middle negative anomaly and no Ce anomaly.The skarn enriches trace elements of Rb，Th and Sm and is depleted of K，Ba，P and Ti，and the marble is lack for Rb and Ba.Obviously，it's typical hydrothermal-metasomatic skarn formed in high temperature，inheriting lithologic features.The formation time of ore-bearing skarn and marbles was 158.1±1.8 Ma.

Key words: Geochemistry, W-Sn Polymetallic ore, Metasomatism, Skarn, Nanshan mining area, Nanling