Structural and thermoluminescence (TL) properties of Gd-doped ZnO nanoparticles were investigated in the present study. TL glow curves recorded in the 10-300 K range presented three overlapped peaks around 56, 110 and 155 K for undoped ZnO nanoparticles. The Gd-doping to the ZnO nanoparticles resulted in shift of peak maximum temperatures to lower values and decrease of activation energies associated with the observed peaks. Activation energies of trapping centers were also reported. Taking into account the previously reported studies on defect characterization of ZnO compound, revealed centers were associated with interstitial defects. Structural characteristics of the synthesized nanoparticles were investigated by x-ray diffraction and scanning electron microscopy measurements.