ABSTRACT: The up-converting ZrO2:Yb,Er nanomaterials were prepared with the combustion and sol-gel methods. FT-IR spectroscopy was used for analyzing the impurities. The crystal structures were characterized with X-ray powder diffraction and the mean crystallite sizes were estimated with the Scherrer formula. Up-conversion luminescence measurements were made at room temperature with IR-laser excitation at 977 nm. The IR spectra revealed the conventional and OH impurities for the combustion synthesis products. The structure of the ZrO2:Yb, Er nanomaterials was cubic except for the minor monoclinic and tetragonal impurities obtained with the sol-gel method. The materials showed red (650-700 nm) and green (520-560 nm) up-conversion luminescence due to the F9/2→I15/2 and (H11/2, S3/2)→I15/2 transitions of Er, respectively. The products obtained with the combustion synthesis exhibited the most intense luminescence intensity and showed considerable afterglow.(Figure is included in full-text article.)