Abstract: A printed circuit board of remote controller occurred corrosion failure. The corrosion failure causes of the circuit board were analyzed by means of macroscopic analysis, scanning electron microscopy analysis, energy spectrum analysis and infrared analysis. The results show that the tin coating in some places of the circuit board of remote controller were missing in the manufacturing process, which lost the protective effect on the substrate, and the substrate occurred oxidation corrosion. The tin coating in some places had high impurity content. With the participation of water vapor, oxygen, carbon dioxide and acid mist in the atmosphere, tin, as the negative electrode of galvanic cell corroded under thin liquid film, lost electrons and occurred electrochemical corrosion. Under the combined action of two kinds of corrosion, the circuit board of remote controller corrosion failure was eventually caused.