Abstract: Tanjianshan gold field,including Jinlonggou middle-large scale gold deposit and Xijingou minor deposit,is lacated at the southeast end of Tanjianshan Mt.,75 km northwest of Dachaidan,Qinghai Province The deposits were formed in three mineralizing epoches:depositional-metamorphic initial enrichment epoch,deformational-metamorphic mineralizing enrichment epoch and magmatic hydrothermal mineralizing superimposed enrichment epoch The ore-forming matter for the former two epoches is from the host strata-gold-bearing formation of the black rock series in Meso-proterozoic Wandonggou group;while for the latter epoch,is mainly from the post-magmatic hydrothermal of late Variscan plagiogranite porphyry complex,and partly from the host strata,from which the ore-forming material is extracted during the magmatic hydrothermal migration