The Yb3+-doped lithium silicate glass is prepared using high-temperature melting process;it is composed of SiO2-Li2O-Na2O-MgO-CaO-BaO-Al2O3-Yb2O3.According to the theoretical and experimental analysis,we obtain the optimum mole ratio of 70SiO2-18Li2O-8MgO-2Al2O3-2Yb2O3,which has the high emission cross section and long fluorescence lifetime.In the system of Yb3+-doped lithium silicate glass,the order of the coordination position reduce with the electric field of the positive ion increased.That is to say that the symmetry of standard position declined.Thus the absorption and launching cross section gradually increase and fluorescence lifetime decrease.