Poly-3,4-ethylenedioxythiophene composite films with tungsten oxide (PEDOT/WO3) were obtained by potentiodynamic deposition of tungsten oxide from acidic metastable solution of isopolytungstatesinto poly-3,4-ethylenedioxythiophene film, pre-deposited on FTO-electrodes. The in situ electronic spectra of poly-3,4-ethylenedioxythiophene-tungsten oxide composite films and their components (poly-3,4-ethylenedioxythiophene and tungsten oxide films) were investigated at different electrode potentials by spectroelectrochemistry. In general, good additivity of spectra of composite films and their individual components allows to conclude that there is no significant specific interaction between the components except electrostatic interaction between positively charged polymer chains and negatively charged tungsten oxide oxo-anions.