Nanometer polycrystal zirconia powder of 11.5-16.5 nm was prepared by explosive detonation technique. The effects of gas oxidation temperature on the properties of the as-synthesized powder were studied by thermogravimetry (TG),differential analysis (DTA) and calcination experiment. X-ray diffraction (XRD)，Raman spectrum and transmission electron microscopy (TEM) were used to characterize the precursor and the as-synthesized product,respectively. The crystal phase composition of zirconia can be controlled through adjusting calcination temperature. The agglomeration problem of product was controlled through shortening growth time.