Indium oxide nanoparticles were prepared in water using a Laser Pulsed Ablation technique in Liquid (PLAL). The Nd:YAG laser was used as an ablation source. The nanoparticles are deposited onto Si wafers by direct overcasting method and also glass substrates covered with Indium Tin Oxide (ITO) by electrophoretic deposition (EPD) method. The optical properties for the colloid (nanoparticles in water) are studied with spectrophotometers. UV–vis spectral analysis showed that the solutions have an absorption edge at 3 eV and average particle size about 30 nm. In order to estimate the particle size of In2O3 in water, the colloidal solutions have been deposited on silicon wafers and imaged by Atomic Force Microscopy (AFM). On the other hand, the Scanning Electron Microscope (SEM) is used to study the topographic nature of the prepared thin film. The results of the spectrophotometric analysis show that the average energy gap and the average particle size of In2O3 nano particles were about 3 eV and about 30 nm; respectively. The interference technique which used to identify the thickness of the films, deposited by electrophoretic deposition, showed that the thickness is about 90 nm. The images of SEM showed that the film, prepared by electrophoretic deposition on ITO substrates, is of porous structure. We observed that the overall process time in this case is much shorter than CVD and PVD.