To investigate the mineralization temperature and material source of quartz vein type gold deposits in the northern Greenstone belt of Madagascar, relatively well developed fluid inclusions were studied in the Maevatananaand the Andriamena quartz vein type gold deposits in the greenstone belt. There are H 2O- NaCl inclusions, namely aqueous solution type (Class Ⅰ); CO 2- H 2O- NaCl inclusion, namely L H 2O +V CO 2 type (Class Ⅱ); CO 2- rich inclusions, namely L H 2O +L CO 2 +V CO 2 type (Class Ⅲ), and a small amount of H 2O- NaCl containing daughter crystals, namely NaCl daughter mineral type (Class Ⅳ). The metallogenic stage can be divided into the early metallogenic stage, the main metallogenic stage and the late metallogenic stage. The early metallogenic stage is dominated by Class Ⅰ and Class Ⅱ inclusions, and occasionally a few Class Ⅳ NaCl subcrystalline inclusions. The main metallogenic stage is mostly dominated by Class Ⅱ and Class Ⅲ inclusions, while the late metallogenic stage is dominated by Class Ⅰ inclusions. The mineralization fluids of Maev and Adm gold deposits are dominated by CO 2- NaCl- H 2O, and contain different degrees of CH 4, N 2 and H 2, as well as a small amount of H 2S volatilization, showing CO 2 rich, medium and low salinity, medium and high temperature immiscibility.Combined with the existing regional geological background and diagenetic ore- forming characteristics, it is inferred that the fluid mineralization is closely related to the formation of a large number of granitic magmas through co- melting or re- melting and the location of upper emplacement; the deposit formation is related to the intrauterine collision orogenic process, and the deep source material is involved in the mineralization.