Valve metals, such as Ta, Nb, and Ti, spontaneously form a passivating native oxide, Ta₂O₅, Nb₂O₅ and TiO₂ respectively, on their surfaces when they are exposed to air and/or aqueous solutions. These surface oxides exhibit high stability, n-type semiconducting properties, and excellent corrosion resistance in most mineral acids. The properties of M|oxide interfaces (where M≡Ta, Nb, Ti) can electrochemically be altered via a deposition of conducting polymers, CPs. In general, among CPs, polyaniline (PANI) was widely studied as, besides its easy, low-cost preparation and adequate stability, it exhibits unique doping/dedoping properties. The electrochemical behavior of PANI is closely associated with its pseudocapacitive properties including moderate to high conductivity, high energy density, and specific capacity. Despite a straightforward electrodeposition of PANI films on conventional substrates (e.g. Pt, Au, carbon), electrodeposition on oxidizable metals (e.g. Fe) and alloys (e.g. stainless steel) is not an easy task. Even more intriguing is the PANI electrodeposition on Ta, Ti and Nb, for which, though only few studies exist, a different PANI redox behavior is reported. Our studies have shown that the redox behavior of PANI thin films on Ta differs as compared with that on Nb and Ti. Two additional cathodic peaks appear at potentials more negative than those where the two-step reduction of the fully oxidized form of PANI appears (-0.2 – 0.8 VSCE). These peaks were never reported for the PANI electrodeposited on other substrates and only the one at higher potentials was previously observed in the case of Ti and Nb. This work focuses on a comparative study of the electrodeposition mechanism of PANI on the M|oxide electrodes aiming to get a further insight into the interfacial features of resulted M|oxide-PANI|PANI electrodes. These features seem to affect the semiconducting properties of the nanocomposite oxide-PANI film as well as the morphology and capacitive properties of PANI films. Specific capacitance of the M|oxide-PANI|PANI electrodes assessed via charge/discharge galvanostatic curves is indicative for their potential application as pseudocapacitors utilizing faradaic reactions.