Oriented (100) polycrystalline thin films of (La, Ce)B-6 with 1 at.% Ce have been deposited on (111) silicon substrates at different substrate temperatures between 600 and 860 degreesC by electron-beam evaporation. Optical reflectivity, X-ray diffraction and electrical resistivity have been systematically studied. The effective optical constants (epsilon, sigma, -Im epsilon(-1), omega(p)) of the (La, Ce)B-6 films are calculated by Kramers-Kronig transformation of the reflectivity spectra and analyzed by a modified Drude model. The results show that the electronic and optical parameters of (La, Ce)B,, films depend on substrate deposition temperature and substrate material. These effects are discussed.