New oxyfluoride glasses and glass ceramic codoped with Nd3+, Yb3+ and Ho3+ were prepared. The x-ray diffraction analysis revealed that the heat treatments of the oxyfluoride glasses could cause the precipitation of (Nd3+, Yb3+, Ho3+)-doped fluorite-type crystals. Very strong green up-conversion luminescence due to the Ho3+: (5F4, 5S2) → 5I8 transition under 800-nm excitation was observed in these transparent glass ceramics.The intensity of the green up-conversion luminescence in a 1-mo1% YbF3-containing glass ceramic was found to be about 120 times stronger than that in the precursor oxyfluoride glass. The reason for the highly efficient Ho3+up-conversion luminescence in the oxyfluoride glass ceramics is discussed.