The Heijintaizi gold deposit is located on the western margin of the Yangtze craton and also on the eastern margin of Tibet. The gold deposit is hosted in Proterozoic plagiaplite and controlled by a NS-trending ductile-brittle shear zone. Gold mineralization occurs mainly as auriferous quartz veins.This paper presents REE analyses of fluid inclusions and quartz which hosts the fluid inclusions as well as auriferous quartz veins. The results show that the REE content of fluid inclusions ranges from 1?846.4×10-12 to 16 003.4×10-12, that of quartz ranges from 2.15×10-6 to 4.35×10-6, and that of auriferous quartz veins varies from 2.59×10-6 to 7.70×10-6. Combined with REE characteristics of host rocks and Kangding complex in the area, the authors hold that REE characteristics of fluid inclusions give some clues to the origin of the ore_forming fluids, which must have been derived fromdeep fluids. The REE of fluid inclusions in quartz were also derived from deep fluids. It is concluded that a careful study of REE in fluid inclusions may playan important role in probing into ore genesis and fluid evolution.