The sheet resistance of indium-tin-oxide (ITO) thin films with different microstructures and morphologies was measured by using a near-field scanning microwave microprobe (NSMM). The NSMM system was coupled to a dielectric resonator with a distance regulation system at an operating frequency f = 5.2-5.5 GHz. ITO thin films with different microstructures and morphology were characterized by X-ray diffraction and atomic force microscopy. As the sheet resistance increased, the intensity ratio of the (222) to the (400) diffraction peak increased and the surface roughness increased. (c) 2006 Elsevier B.V. All rights reserved.