The structure around Ti4+ in BaO-SiO2-B2O3-TiO2 had been studied by X-ray fluorescence spectra. The results show that the Ti4+ mainly exists in the ［TiO4］ and enters the network of ［SiO4］. ［TiO4］ has the tendency to change to ［TiO6］ with the increase of TiO2 content. When the TiO2 content increases to about 20mol% the tendency reaches its maximum.