Ionic conductivity values as a function of temperature and iodine pressure in compact and adherent PbI2 film grown on pure Pb have been estimated from the isothermal parabolic rate constants through tarnishing study under short-circuit condition. Iodide films have been grown inside a specially designed iodination reactor in the temperature and iodine pressure ranges of 423-523 K and 0.615-6.578 kPa, respectively. Estimated ionic conductivity values have been found to follow a pressure dependence relation of the type sigma(i) = sigma(i)(0) x P-I2(1/3) associated with an activation energy value of 51 kJ.mol(-1). The iodide film has been characterized by SEM and EPMA analyses.