Abstract: Yanshanian meta-alkalic intermediate-weak alkalic magmatic rocks, which are controlled by regional tectonics, are broadly spread in Tarshan area, Southern Shanxi Province. The magmatic rocks show evident progressive evolution in petrology and petrochemistry with four-phased intrusions. The first phase intrusive syenodiorite is the major parent rock for the iron deposits in the area. The magmatic rock is controlled by the interformational structure of Middle Ordovician magnesian carbonate strata. Magma intruded along beds and possibly formed multi-layers of ore. The ore is skarn type in genesis, mainly controlled by the magmatic rock, the intruded carbonate rock and the interformational structure. The magmatic rock played an important role in the metallogenic process. Based on features of the magmatic rock and its control on the ore, together with the magnetic anomalies, the authors put forth ore-searching directions in the area.