Nanometer sized lead molybdate (PbMoO4) plates are prepared through conventional hydrothermal together with sonochemical methods. The plates are then characterized using field-emission scanning electron microscopy, X-ray diffractometry, Fourier transform infrared (FTIR) spectrometry, photoluminescence spectrometry, and ultraviolet-visible (UV-VIS) spectrometry. The results indicate that the nanoplates have a characteristically narrow particle size distribution and their tetragonal scheelite-type structure is confirmed by both X-ray diffractometry and FTIR spectrometry. When the nanoplates are compared with the corresponding bulk crystals, blue shifts in their photoluminescence peaks, wider optical band gaps, and the broadening of the X-ray diffractometer peaks are observed. These can be ascribed to the decrease in crystal size.