Corrosion behavior of zinc in a simulated acid rain has been investigated by electrochemical impedance spectroscopy, atomic emission plasma spectroscopy and X-ray photoelectron spectroscopy. It was found that corrosion rate increases drastically in the solution of lower pH near 3. Corrosion potential shifts to less noble value with increasing pH at the lower pH 2.5 and shifts to more noble value at the higher pH 2.9. An oxide film of about 1 mu m thick is revealed on zinc surface at pH 3.6, and no film is detected at pH 2.1. Electrochemical impedance diagram has an inductive loop for the solution of higher pH 3.2, while only depressed capacitive-loops are observed at pH below 2.9. The magnitude of the impedance diagram rises with the increasing period of immersion at higher pH 3.2, and decreases at lower pH 2.3. The phenomena observed are discussed in terms of Zn2+ diffusion rate and change in the oxide film thickness.