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The photosensitization is a powerful method used to extent the photoresponse of a wide-bandgap semiconductor into the visible region of the spectrum. These process has a paramount importance in application for solar energy conversion. The photocurrent spectroscopy was used to study heterogeneous photoelectrodes of the porous $WO3$ film/nanoparticulate $TiO2$ film. Dependencies on wavelengths and applied potential were investigated in order to explore the charge photogeneration process. Photocurrent spectra and cyclic voltammogramms are recorded in a three-electrode cell. The source is 400 W Xe lamp coupled to a SPEX monochromator. The monolayer of adsorbed dyes (cresyl violet, thionine and rhodamine B) was used for photosensitization process. The nanoparticle size, film morphology and structure were tested with scanning and transmttance electron microscopy. The density and thickness of the deposited films were determined with a Electrochemical Quartz Crystal (EQCN). The band gap energy for $WO3$ and $TiO2$ films was determined from the spectral distribution of photocurrent. The comparative analysis of photoelectrochemical properties of $WO3/TiO2$ heterogeneous photoelectrodes and one-component photoelectrodes of $WO3$ and $TiO2$ has been carried out at the front side illumination of the films. A very promising increase of photocurrent (in the 2-10 times) in heterogeneous photoelectrodes at supraband illumination and subband illumination with photosensitization by adsorbed dyes was observed. The heterogeneous structure of porous nanocrystalline $WO3$ oxide films/nanoparticulate $TiO2$ film allows one to improve charge separation process and increase photogeneration efficiency. Improvement of charge separation can be expected due to electron transfer from conduction band of $TiO2$ nanoparticles to the lower lying conduction band of nanocrystalline oxide film.