Abstract: Taking Yaochong Mo deposit as the research object，the metallogenic material sources are discussed by analyzing the S and Pb isotope compositions characteristics of sulfide ore. The research results indicated that，the δ^34S values of ore range from -2.89‰ to -1.6‰，and its isotope compositions owns tower distribution. It is inferred that，the isotope material sources are single and the ore has the characteristics of magmatic sulfur. The δ²⁰⁶Pb/δ²⁰⁴Pb value of sulfide minerals varies from 16.193 to 16.818,δ²⁰⁷Pb/δ²⁰⁴Pb value of sulfide minerals varies from 15.105 to 15.288，δ²⁰⁸Pb/δ²⁰⁴Pb value of sulfide minerals varies from 36.698 to 37.319，that is，the isotopic composition ranges narrowly. The μ value of Pb isotope in the ore deposit is low and its distribution is relatively concentrated，but ω value of Pb isotope is high，indicating that the lead isotope derives from the lower crust. According to the comprehensive analysis results of the mineralization geological background，geological characteristics and the exiting ore deposit genesis of Yaochong Mo deposit，it is concluded that，the porphyry mineralization of Yaochong Mo deposit come from the granitic magma that derive from the partial melting of the thickening lower crust. Yaochong Mo deposit belongs to the porphyry molybdenum deposit that is associated with lower crust molten role，and the minerals come from the lower crust.

Key words: Yaochong Mo deposit, S isotope, Pb isotope, Geological implication