A study of the optical properties of Pr3+-Yb3+ ions in oxyfluoride glass and glass ceramics was carried out. The cross section emissions at 1300 nm corresponding to the 1G4 →3H5 transition of Pr3+ ions were obtained. The ceramming process reduced the linewidth of this transition by about 12% and the emission stimulated cross section was increased by a factor of 1.4 compared to the precursor glasses. The mean wavelength is nearly constant (about 1325 nm) above room temperature. After analyzing the luminescence decay curves of Yb3+ ions, it was found that the majority of the optically active ions in the glass ceramic were located in the fluoride nanocrystals and the rest in the glassy phase. The shortening of distances between the ions turns the energy transfer process into Yb3+ → Pr3. However, emission at 1300 nm Pr3+ was concentration quenched.