[en] The Tm³⁺/Yb³⁺ codoped alumina lead borate glasses were prepared by the conventional melt quenching technique. Optical absorption and FTIR spectra were recorded. The upconversion fluorescence spectra exhibited weak blue (480 nm) and intense red (660 nm) emissions due to ¹G₄ → ³H₆ and ¹G₄ → ³H₄ transitions, respectively. The results concluded that both emissions are due to three photon absorption process. It has been observed that in the upconversion efficiency increases with the increase in the concentration of Yb³⁺ ions. The strong red upconversion fluorescence indicate that Tm³⁺/Yb³⁺ codoped alumina lead borate glasses can be used as potential host material for upconversion lasers. (paper)