Er3 + /Yb3 + co-doped TeO2-WO3-Bi2O3 (TWB) glass has been prepared.The absorption spectra, fluorescence spectra and up-conversion luminescence of the glass were measured. The strength parameters of Er3+ in glass were calculated according to the Judd-Oflet theory. Along with Bi2O3 content increasing, Ω2 increases, Ω4, and Ω6 gradually decrease. The broad 1.5 μm fluorescence was observed under 976 nm excitation, and its full width at half maximum (FWHM) was 96 nm. The stimulated emissiow was calculated using the McCumber theory, and the peak emission cross-section was 0.70 × 10-20cm2 at 1.5 μm. The product of stimulated emission cross section and fluorescence of FWHM was 60.2 cm2 nm. At the same time, there is an obvious phenomenon of fluorescence up-conversion of Er3 +/Yb3 + co-doped TeO2-WO3-Bi2O3 glass under 976 nm pump, and the intensity of the conversion gradually weakened with the increasing of Bi2O3 content.