A new Er3+-doped tellurite glass has been studied. According to the a bsorp tion spectrum, Judd-Ofelt intensity parameters were determined and used to calcu late the radiation rates, fluorescent branch ratio and radiative lifetimes of Er 3+ in Er3+-doped tellurite glasses. The J-O parameters wer e o btained as follows, Ω2=479×10-20cm2,Ω 4=152×10 -20cm2,Ω6=070×10-20cm2. The stimulated emission cross-sections (σ e=1040×10-21cm2)， of the Er3+ io n 4I13/2→ 4I15/2 transition was calculated using the McCumber th eory. The FWHM(FWH M=655nm) of the 4I13/2→4I 15/2 emission and lifetimes of every level of Er3+ ion were measured and the lifetime of 4I1 3/2 level obtained is 399ms. The spectroscopic properties of Er3+ ion were compared with those in different glasses. These studies indicate that tellu rite glass is much more beneficial for optical fiber amplifiber to realize broad band and high gain amplification.