In Situ high-resolution FT-IR and Raman Spectroscopies combined with electrochemical analysis have been applied to the study of the electrochemical interface between the electrode and electrolyte solutions. This combination has proved to be advantageous for studying the reactions in the interfacial reaction field between the electrode and electrolyte solutions. These techniques, referred to as FT-IR and Raman spectro-electrochemistry, reveal the vibrational spectro-electrochemistry at the electrochemical interface under potentiostatic conditions. This paper describes that the in situ spectro-electrochemistry is a powerful tool for investigating electrochemical interface.