Allophane-titania nanocomposite electrodes were prepared from titanium alkoxide sols dispersing the natural clay mineral allophane. Electrochemical measurements indicated that the oxidative degradation of glucose in the electrolyte enhanced the generation of electricity during UV irradiation. A higher short-circuit current was observed in the photofuel cell using the 0.10% allophane-containing titania electrode than that with the normal titania electrode. Allophane effectively adsorbed the glucose molecules and then transported them to the titania, on which their oxidation induced the electrogeneration.