Recent studies on pressure-induced structural changes in silicate glass (melt) by various spectroscopic techniques are reviewed. The following changes have been observed with increasing pressure; reduction of Si-O-Si angle, change in Qⁿ distribution, and formation of high-coordination Si (Si^v and Si^VI). Systematic change of high-coor-dination Si with pressure and composition reveals that high-coordination Si is produced by consuming non-bridging ox-ygens in alkali-silicates. The importance of Si^v for dynamic process is discussed.