Jiudian is a representative quartz vein-type gold deposit in the Jiaodong world-class gold province, southeast of the North China Craton. Four stages and ten pyrite generations can be identified based on the paragenetic relationships: (1) pyrite (Py1)-milky quartz, (2) pyrite (Py2-1 and Py2-2)-smoky grey quartz, (3) siderite-pyrrhotite-pyrite (Py3, Py3-1 and Py3-2)-quartz, (4) quartz-polysulfide-siderite-marcasite (Py4-mc)-pyrite (Py4-1, Py4-2 and Py4-3), suggesting the complex and multistage ore-forming processes.The course-grained euhedral Py1 from the pre-ore stage 1 quartz veins is enriched in lattice-bound Co, Ni, and Se with relatively low δ34S values (+4.7 to + 5.5‰), precipitated from the equilibrated fluid environment with higher temperature (ca. 400 ℃). The dissolution-reprecipitation textures are characterized by the pristine As-rich Py2-1 as parent phase and porous Py2-2 as product phase hosting abundant microscale galena enriched in low-melting chalcophile elements (LMCE, e.g., Pb, Bi, Ag, Te, and Sb) and minor electrum. Both of Au-HS and Ag-Cl complexes destabilized by decompression would result in the precipitation of electrum with low gold fineness (672 to 713). Py3 is a poor host for majority of trace elements coexisting with pyrrhotite, precipitated from the late second pulse fluid.Py3 was overprinted by the third ore fluid pulse and replaced by siderite into sieve-shaped Py3-1 and anhedral aggregates Py3-2. Subsequently, fluid oxidation caused by pyrite replacement and meteoric water influx would result in the precipitation of marcasite (Py4-mc). Furthermore, euhedral pyrite aggregates were directly deposited from this ore-forming fluid, characterized by the Co-rich core (Py4-1) with abundant inclusions of LMCE-dominant sulfosalt (lillianite homologues) and galena, overgrown by pristine As-rich rim (Py4-2). The decoupled As and Co in Py4-1 and Py4-2 were probably attributed to abrupt temperature drop due to meteoric water influx. Nevertheless, the precipitation of visible gold with higher gold fineness in siderite or intergrown with Py4-mc was primarily resulted from fluid oxidation which has significant effect on the stabilities of Au-HS complexes but little on those of Ag-Cl complexes. The last generation Py4-3 was the post-oxidation product, evidenced by the extremely negative δ34S values (-34.3 to −28.4‰).Hence, the textural and geochemistry characteristics of different pyrite generations of Jiudian have revealed the presence of three fluid pulses as well as the distinctive evolution processes and changes of physicochemical conditions leading to the characteristic mineral assemblages and multiple-stage gold mineralization, which could provide implications for the genesis of siderite-rich gold deposits in the Jiaodong district.