The photoluminescent properties of nanocrystalline ZrO

2

:Dy

3+

powders were studied in this paper. We observed the room temperature sharp characteristic emission of Dy

3+

its concentration quenching and the energy transfer between the nanocrystalline ZrO

2

host and the rare earth ion Dy

3+

. The sintering temperatures gave appreciable influence on the crystalline phases of the nanocrystalline ZrO

2

. As the sintering temperature was changed

the crystalline phase was also changed

which made the characteristic emission of Dy

3+

obvious different. It is shown that there exist two emission centers for the rare earth ion Dy

3+

which occupy different crystalline phases produced by calcining samples at different temperatures. The studies on the effect of the doped Dy

3+

concentration on the fluorescence emission intensity show that there exists the concentration quenching phenomena of the rare earth ion Dy

3+

in the nanocrystalline ZrO

2

host. The optimum doped concentration depends on the crystalline phase of the host. Different crystalline phases cause different quenching concentration. The optimum concentration for the luminescence Dy

3+

is determined to be 0.5% for the tetragonal structure and 1% for the mixture crystalline phases. The energy transfer process also depends on the crystalline phase of the host. The energy transfer efficiency is the most highest for the 950℃ sample. A model for microscopically explaining the energy transfer processes between the nanocrystalline ZrO

2

host and Dy

3+

was given.