The effects of hydrogen on the types, morphologies  and electrochemical properties of the surface films formed on iron in aerated pure water at 25, 40, 50 and 70 ^oC were investigated by  by using optical microscopy, X-ray diffraction measurements, Raman spectroscopy, electrochemical impedance spectroscopy (EIS) and Mott-Schottky (M-S) plots. Increasing temperature from 25 ^oC to 70 ^oC significantly accelerated the corrosion of non-charged iron. Figure 1 shows that yellow rust formed on the non-charged iron after immersion 21h at 40 ^oC, while the surface of hydrogen-charged iron after immersion in the same condition was gray. Figure 2 shows that the film formed on the non-charged iron after immersion 21h at 70 ^oC was dark, while the surface of hydrogen-charged iron after immersion in the same condition was covered with loosely distributed yellow rust particles. Raman spectra showed the different compositions of formed films on non-charged and hydrogen-charged iron specimens, as shown in Fig. 3. Normally the high valence iron oxides were formed on non-charged iron while relative low valence iron oxides were formed on the hydrogen-charged iron, with exceptions. The stability and semiconductor properties of the surface films formed on non-charged and hydrogen-charged specimens were characterized by EIS and M-S plot measurements in boric acid-borate buffere solutions, showing significant effect of hydrogen.