The structures and chemical compositions of feldspar surface silica glazes from the Holocene volcanic eruptive material at the Tianwen peak, Tianchi, Changbai Mountains was studied using SEM and EDX. The result shows that silica glazes of varied structures developed on feldspar surfaces in the pumices on the Tianwenfeng cross section, which change in color from black at top downward to dark-grey at bottom. Their structural features vary with the ages of volcanic eruption. Early eruption of volcanic rocks resulted in thicker silica glazes and more complicated structure on the surface of feldspar grains; late eruption formed thinner glaze and simpler structure. Such a composition indicates that the glaze resulted from deposits of dissolved silicate. And the correlation between the composition of silica glaze and the elements is analogues to that of the glaze rich in fragment determined by Dorn in 1998.The features of these structure and variety of the compositions reflect the processes of rock weathering, migration and final deposit.