Abstract: In China, the largest gold concentration area is Jiaodong, in which the genetic type of gold deposits has always been controversial.Heilangou gold deposit is the largest one in Penglai area of Jiaodong and was well-known for producing gold nugget.In this paper, LA-ICP-MS was used to analyze the composition, variation trend and correlation of trace elements in pyrite of Heilangou gold deposit, and to discuss the formation of Au.Through field investigation, combined with mineralogy and backscatter electron image(BSE), the pyrite(Py1~Py3)in the main metallogenic stage(S1~S3)is divided into six subtypes.Through trace element analysis, it is found that the change trends of Cu, As, Ag, Au, Zn, Co, Ni, Pb, Sb and Bi are inconsistent from early to later stage.As and Au show strong positive correlation in every pyrite subtype, Cu-Zn, Ag-Sb and several other element pairs have high correlation, Pb-Bi has an upper correlation especially in three subtypes of Py1-1, Py2-1 and Py2-2, and also Co-Ni in most pyrite subtypes.The Co/Ni ratio is mainly in the range of 1.1 ~ 3.3, which indicates that the pyrite is mainly of magmatic hydrothermal origin.The ore-forming fluid of Heilangou gold deposit is rich in Au-As, and the trace elements are relatively enriched in S1 and S3 stages, which indicates that the ore-forming fluid activity lasts for a relatively long time and has the pulsating characteristics.Gold is precipitated by the fluid rich in Au-As for multiple activities and several times.