We have studied the effect of electron gun power and substrate temperature on the properties of nanocrystalline ceria thin films using electron beam evaporation method. The ceria films were grown on the glass substrate and characterized using different techniques such as: X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Raman spectroscopy and UV-visible spectroscopy measurements. It was observed that electron gun power has influence on the crystallite size which increases (from 5 to 11 nm) as the gun power increases. Also, the crystallite size increases from 8 to 22 nm by increasing substrate temperature from room temperature (RT) to 400 degrees C. The FE-SEM images show that all the films have nanocrystalline growth. From the Raman spectra, we have observed two peaks at 466 and 565 cm(-1). The peak at 466 cm(-1) is assigned to the presence of the F-2g mode of CeO2 whereas the peak at 565 cm(-1) is due to the presence of the oxygen vacancies. UV-visible measurements reflect that all the films have high transparency, more than 80% in the visible region. (C) 2010 Elsevier B. V. All rights reserved.