The electrical behavior of a supported inorganic film (hydrogen uranyl phosphate or UPP) in contact with electrolytes containing inorganic precipitate generating ions was studied by ac and de measurements. The equivalent circuit for the system UO2(NO3)(2)/UPP film/H2O3PC6H5 was determined by impedance spectroscopy. This technique permits us to obtain three different electrical contributions for the whole system : (i) film/electrolytes interface; (ii) bulk film; (iii) electrolyte solutions. Film and interface electrical parameters, such as the film resistence and capacitance (R(f) and C-f(eq)), the charge transfer resistance (R(ct)), and double layer capacitance (C-df(eq)), were obtained for different concentrations of the external solutions. For comparison, measurements with the same electrolytes at both sides of the UPP film were also made. From de measurements the asymmetry of the current-voltage curves, depending on the polarity of the external voltage applied to the system, was also obtained. This asymmetry can be taken as a measure of the him efficiency for electric current rectification. Concentration dependence for the i-v curves was also considered.