The transport and recombination of electrons in dye-sensitized TiO2 solar cells were studied by anal. of the current and voltage response to a small square-wave light-intensity modulation. Solar cells were studied under working conditions by using potentiostatic and galvanostatic conditions. An increase in applied voltage, i.e., from 0 V toward open-circuit voltage, was found to lead to faster electron transport at low light intensities, while it slowed transport at higher light intensities. This observation seems to be conflicting with the multiple trapping model with diffusive transport. An effective diffusion length at the max. power point was calcd., and it was shown that it decreases with increasing light intensity.