Jiaodong is the most important concentrated exploration area for gold deposits in China. During the 14th Five Year Plan period, Shandong gold geology and mineral exploration Co., Ltd. explored another super large gold deposit -- Xiling gold deposit between Sanshandao-Cangshang fault zone. Its accumulated detected gold resources reach 580t, with an average grade of 4.24 g/t, making it the largest single gold deposit discovered in China at present. It is located between the Sanshandao gold deposit and the northern sea area gold deposit. It is the deep extension and lateral part of the Sanshandao gold deposit in the northeast direction, and is connected to the northern sea area ore body in the deep. In fact, the three are actually the same ore body. Xiling gold ore body controls a maximum strike length of nearly 2000m and a maximum extension depth of 2057m; it is found that the ore body is in the form of "short handled axe" inclined to the Northeast in the horizontal direction, and has obvious echelon in the vertical distribution. The gold resources are mainly concentrated at the elevation of -1000 ~ -2200m; At the northeast end of the mining area, the ore body has extended to - 2600m, and continues to go deep. The thickness of the ore body becomes thinner, the grade is low, and the deep gold mineralization becomes weaker; The ore body extends from shallow to deep in multistage steps, which generally shows the characteristics of steep and gentle alternating echelon mineralization. Through the study of fluid inclusions in the deposit, it is found that the gold ore-forming fluid belongs to H2O-CO2-nacl fluid with medium temperature (199 ~ 347 ℃) and medium and low salinity (0.35 ~ 8.28 wt.%) rich in CO2, which is consistent with the large-scale gold ore-forming fluid in Jiaoxi North University, but slightly different in the process of gold deposit precipitation and migration. The precipitation mechanism of Xiling gold is mainly fluid immiscibility, and the temperature and salinity of the fluid in the main metallogenic period change most obviously, from the shallower part to the later stage of mineralization, The properties of ore-forming fluids tend to be more uniform. There is a certain coupling relationship between the emplacement of fluids and the spatial echelon mineralization. Gold mineralization is mainly concentrated in the second and third echelon spaces, corresponding to the middle and late stages of the mineralization stage. The study of S isotope shows that pyrite δ34S value has the trend of first increasing and then decreasing. The initial sulfur source of Xiling gold deposit may be closer to magmatic sulfur. In the process of mineralization, ore-forming materials and ore-forming fluids were mixed with other sources. The gold ore in the area has experienced strong assimilation, mixing and alteration metasomatism. The main element SiO2 is moderately acidic, with high Al2O3 and K2O and low Na2O、 TiO2、 MgO and CaO. It is peraluminous potassic basalt and high potassic calc-alkaline series granite. The ree distribution form is right-leaning type enriched in LREE, enriched in large ion lithophile elements (LILE) and depleted high field strength elements (HFSE), which has similar geochemical characteristics with island arc magmatites in extensional tectonic setting. Comprehensive studies have shown that,Xiling gold deposit belongs to altered rock type gold deposit formed by mesothermal magmatic hydrothermal filling metasomatism according to its genetic type. It was formed in the extensional tectonic background under the failure mechanism of North China Craton in the early Cretaceous. In the early Cretaceous, lithosphere thinning and asthenosphere upwelling caused large-scale magmatic activity. The coupling of structure, magma and fluid created large-scale gold mineralization in this area.