Ultramafites in the Songshugou area, Shangnan county, Shaanxi Province, to the north of the Shangzhou—Danfeng fault is the largest Alpinetype ultramafic massif in China. Covering an area of about 20 km2，and it is contact with the Qinling Group as intrusions. The rockbody is composed mainly of finegrained dunite, medium dunite and harzburgite. Geochemical characteristics show ultramafites are depleted, while rocks from the Songshugou dunite body display clear enrichment of highly incompatible elements (Rb to Nb) and LREE compared HREE. The PGE concentrations of dunite are lower than harzburgite obviously. Compared with ophoplitic mantle peridotite, we propose that the Songshugou body is the product of peridotite with melt through melt percolation.