The Er3+-doped TeO2-WO3-ZnO-ZnF2(TWZOF) glasses were prepared. The absorption spectra, 1.5 μm emission spectra and fluorescence lifetimes of Er3+, excited at 970 nm, were measured. The J-O parameters Ωt (t=2,4,6), absorption and emission cross-sections were calculated by Judd-Offelt theories and McCumber theory, respectively. The dependence of the content of ZnF2 in glass composition upon 1.5 μm emission intensity, fluorescence lifetime and bandwidth of Er3+ was investigated. In TWZOF glass, Er3+ ion had a large emission cross-section with a peak value of 0.86 pm2. Er3+ ions also had a broad 1.5 μm emission spectrum in the glass, which had a FWHM between 68 nm and 83 nm. The maximum FWHM demonstrated here was 83 nm. Er3+ ion had a large value of Ω6 and a small value of Ω2 in TWZOF glass. With the increasing of the content of ZnF2, The Ω2 and the Ω6 both increased. The emission intensity at peak wavelength and the fluorescence lifetime of Er3+ at 1.5 μm also increased with the increasing of the content of ZnF2.