There exist large numbers of primary inclusions in quartz phenocrysts within topaz granitic porphyry from Yangbin, Zhejiang Province. Based on large quantities of analytical work in such aspects of the inclusions as their homogenization temperature, salinity and chemical composition, the authors have classified these primary inclusions into five major types, namely melt inclusions, hydroxylated silicate melt fluid inclusions, nonhomogeneous captured polyphase inclusions, liquid inclusions (including high salinity liquid inclusions and low salinity liquid inclusions), and gas inclusions. In addition, the formation mechanism of inclusions in this area are studied with respect to magmatic stage, magmatic disaggregation stage, magma/fluid immiscible stage, and hydrothermal dominant stage, thus convincingly supporting the opinion of magmatic origin for topaz granitic porphyry.