A simple and facile hydrothermal route has been demonstrated for the shape-selective preparation of highly crystalline Gd2O2S:Eu3+ nanostructures, such as nanocrystals/nanoplates, nanosheets, nanobelts, nanotubes, nanorods, and nanowires are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), photoluminescence (PL) techniques. The as-prepared samples are characterized using X-ray photoelectron spectra (XPS), to investigate the elementary states on the surfaces. The concentration of precursor chemicals, pH, the reaction time, and the temperature are important factors in the morphological control of Gd2O2S:Eu3+ nanostructures. The adjustment of these parameters can lead to an obvious shape evolution of products. The origin and nature of the opto-electronic transitions were observed using opto-impedance measurements.