Abstract <p>The results of complex mineralogical and geochemical studies of Upper Permian terrigenous rocks of the orogenic Khangalas gold deposit in the Yana‒Kolyma belt are reported. The petrographic and lithochemical characteristics of the rocks are typical of polymictic sandstones (graywacke), oligomictic graywackle siltstones, and mudstones. The terrigenous component of the Upper Permian sediments is a product of erosion of rocks with a predominant acidic and less basic composition, as well as graywacke. The presence of a volcanogenic material is characteristic. The formation of thick units of polymictic sandstones (graywacke) with interlayers of oligomictic siltstones and mudstones is related to the high-rate sedimentation in delta complexes and periodic sea-level fluctuations. The changing redox conditions of the bottom water were a favorable factor for mobilization of ore elements and formation of diagenetic sulfide mineralization of rocks. The regional and dislocational metamorphism processes are characterized by the removal of Si⁴⁺, Al³⁺, Ca²⁺, Fe²⁺, and Mg²⁺ into the pore space and by enriching the interporous expelled water with these elements. Hydrothermal changes involved the supply of Al³⁺, Ca²⁺, Fe²⁺, Mg²⁺, Sb, Au, Ag, Co, Ni, Cd, and Te and the formation of geochemical associations of Au with chalcophylic (As, Sb, S, and Cd) and lithophylic (Na, Ca, P, Mn, Be, Mg, and W) elements. The connection of Au with a group of newly formed minerals (pyrite, arsenopyrite, siderite, and sericite) is emphasized. The increased concentration of W and Mo indicates their entry in the composition of the high-temperature fluid related to a magmatic source characteristic of the superimposed Ag‒Sb mineralization. The lithogenesis processes contribute to the formation of the mineralogical and geochemical specialization of the host rocks, favorable for the occurrence of disseminated mineralization with isomorphically bound gold at the Khangalas deposit. The results obtained are important for the truthful understanding of the effect of the environment on the ore formation conditions in slightly metamorphosed complexes of collisional terranes and forecasting orogenic gold deposits.</p>