Erbium-doped glass showing the wider 1.5-um emission band is reported in a novel oxide system TeO_{2}-WO_{3}-Nb_{2}O_{5} and their thermal stability and optical properties such as absorption, emission spectra, cross-sections and fluorescence lifetime were investigated. Compared with other glass hosts, the gain bandwidth properties of Er^{3+} in TWN glass is close to that of bismuth glasses, and larger than those of tellurite, germanate, silicate and phosphate glasses. The broad and flat ^{4}I_{13/2}-->^{4}I_{15/2} emission and the large stimulated emission cross-section of Er$^{3 + }$ ions around 1.5um can be used as host material for potential broadband optical amplifier in the wavelength-division-multiplexing (WDM) network system.