Er3+ singly doped and Er3+/Nd3+-codoped fluorotellurite glasses are prepared by melt-quenching method. The Judd–Ofelt intensity parameters (Ωλ,λ=2, 4, and 6), radiative transition rate (Arad), and radiative lifetime (τR) of Er3+ are calculated based on the absorption spectra. The 2.7μm emission spectra of Er3+ ions in fluorotellurite glasses are investigated under 808nm excitation. The enhancement of Er3+ 2.7μm emission shows that Nd3+ can be an effective sensitizer for Er3+: 4I11/2→4I13/2 transition, and the energy transfer efficiency can be as large as 84%. The absorption and emission cross sections are calculated using Füchtbauer–Ladenburg equation and McCumber theory with large values of 1.62×10−20cm2 and 1.11×10−20cm2, respectively. The results suggest that the present glasses have potential applications in 2.7μm laser materials.