Near-stoichiometric Er∶LiNbO3 has many properties superior to the co ngruent one and has aroused extensive interest. It was obtained by the technique of vapor transport equilibration (VTE), its optical properties, including OH- absorption spectra, transmission spectra, emission spectra and the position of absorption edge were studied. The higher transmittance, the narrower of the peak width, the “blueshift" of the optical absorption edge, as well as the significant reduction of the OH- absorption band are indicative of the VTE treatment having brought the crystal closer to the stoichiometric composition. We also observed the increase of Er3+ luminescent intensity, and predicted that the VTE treatment must lead to the increase of fluorescence lifetime. The possible modification of materials in amplifier, self-frequency doubling laser and waveguide laser etc were expected.