The Yb3+/ Er3+ co-doped and Er3+ single doped oxyfluoride glasses were prepared by high temperature melting method. The optical properties of the samples were studied. According to differential thermal analysis (DTA) curve, the samples were thermal treated at 552 ℃, and micro-crystalline were formed after thermal treatment. The near infrared luminescence spectra under 980 nm excitation of the samples were recorded at room temperature. The results showed that the near infrared luminescence intensity increased with increasing Yb3+ concentration. This is because Yb3+ ions absorbed pumped energy of 980 nm through 2F7/2→2F5/2 transition, and then the energy was transferred to Er3+ ions by the way of resonance energy transfer and enhanced the 4I15/2→4I11/2 transition.