The spray pyrolysis technique was employed to prepare lanthanum selenide (La2Se3) thin films on ordinary glass and fluorine doped tin oxide (FTO) coated glass substrates under optimized conditions. The preparative parameters are optimized to get good quality of La2Se3 thin films. X-ray diffraction (XRD) study reveals that only cubic La2Se3 is formed with a grain size of about 42 nm. The direct optical band gap is estimated to be 2.6 eV. The dispersions of dielectric constant and dielectric loss are studied with the variation of frequency. The room temperature electrical resistivity of the films is found to be of the order of 10(5) Omega cm. The film is found to be a p-type semiconductor. (C) 2003 Elsevier Science B.V. All rights reserved.