In this paper, a tetrazole derived diamine ligand of 2-(1H-tetrazol-5-yl)pyridine (TP) owing electron-donors and short conjugation chain was synthesized to increase the band gap of its corresponding phosphorescent Cu(I) complex. This Cu(I) complex was characterized in detail, including its single crystal structure, singlet electronic transitions, photophysical parameters, thermal stability and electrochemical property. Upon on photoexcitation, this Cu(I) complex emitted green emission peaking at 497nm with biexponential decay pattern of τ1=5.5414μs (A1=0.137) and τ2=1.0679μs (A2=0.11503). Cyclic voltammerty experiment suggested that this Cu(I) complex owned HOMO and LUMO energy levels of −5.79eV and −2.39eV. The thermal decomposition temperature was 170°C as indicated by thermogravimetric analysis. The optimal electroluminescence device constructed by solution processed coating procedure showed green electroluminescence peaking at 525nm, with maximum luminance of 2860cd/m2 and maximum current efficiency of 5.9cd/A.