Laser flash induced photocurrent transient measurements were used to study the electron transport in nanostructured TiO2 (anatase) thin film electrodes in contact with an electrolyte. The shape and the time domain for the current transients are dependent on film thickness and electrolyte cond. The exptl. results are discussed using a diffusion model. If the exptl. results are interpreted as diffusion, a chem. diffusion coeff. for the electrons in the nanostructured system was detd. to 1.5 × 10-5 cm2/s using 700mM LiClO4 in ethanol as electrolyte.