Absorption spectra, emission spectra and fluorescence lifetime of Er3+ions were measured for TeO2-ZnO-Na2O-K2O glasses w ith different doping concentrations of Er3+ and the emission cross section σe of Er3+ was calculated. Dependence of luminescence intensity and fluorescence lifetime on concentration of Er3+ were analyzed. The influence of concentratio n of Er3+ ions on luminescence intensity and fluorescence lifetime was unc onspi cuous in the case of low doping level of Er3+. However, high concentr ation of Er3+ ions resulted in the concentration quenching, which reduced the l uminescence intensity and fluorescence lifetime. The optimum concentration of Er3+ ions was determined for TeO2-ZnO-Na2O-K 2O glasses, and the mechanism of concentration quenching was also discussed and explained in detail.