The Chaypareh granitic–gabbroic intrusive bodies are located in the Sanandaj–Sirjan structural zone, 35 km northwest of Khoy city, Iran. Petrographic studies indicate that the granitoid mass consists of felsic igneous rocks, including alkali feldspar granite, granodiorite, syenogranite, and monzogranite, as well as mafic rocks such as diorite and gabbro. The main rock-forming minerals are quartz, plagioclase, and K-feldspar, along with biotite, amphibole, sphene, and opaque minerals. Various textures, including granular, graphic, perthitic, and myrmekitic, are observed. Plagioclase compositions range from oligoclase to andesine. Biotites are primarily magmatic, primary, and calc-alkaline in nature. The amphiboles are compositionally classified as magnesiohornblende and are interpreted to be of magmatic origin. Thermobarometric studies of biotite and amphibole suggest that the magmatic reservoir of the granitoid rocks was located at a pressure of approximately 0.65–2 kbar, a temperature range of 650–900°C, and a depth of 2–7 km. Mineral chemical characteristics, geothermobarometric data, and the occurrence of primary magnetite collectively indicate that the magma crystallized under relatively oxidizing conditions with moderately high oxygen fugacity. Integrated mineralogical, mineral chemical, and thermobarometric evidence suggests that the Chaypareh granitoid was derived from an I-type calc-alkaline magma and evolved in a post-collisional tectonic setting influenced by subduction-related processes.