Abstract: In order to develop ytterbium-doped core material of high-power fiber lasers, lithium silicate glass samples with ingredients 0.70SiO₂-0.18Li₂CO₃-0.04MgCO₃-0.04BaCO₃-0.02Al₂O₃-0.02Yb₂O₃ (mole fraction) were prepared by the method of high temperature melting. Absorption spectrum in the range of 850nm~1100nm and fluorescence spectrum under excitation wavelength of 858nm were measured. Spectral and laser property parameters were theoretically calculated by using experimental data. The results demonstrate that the main fluorescence line with 1036nm wavelength has effective width of 94.1nm, absorption cross section of 1.143pm², emission cross section of 1.024pm² and fluorescence lifetime of 0.98ms. The least population of the exciting state is only 0.042 and the most minimal pump intensity is 0.76kW·cm^-2. Compared with the recently reported Yb³⁺-doped laser glasses, the glass samples with these parameters are advantageous. This kind of Yb³⁺-doped lithium silicate glass is hopeful to apply in the preparation of Yb-doped fiber cores.