Titanium oxide nano-networks, which have various crystal structures, were fabricated by the sol-gel polymerization in an organogel formed by L-isoleucine organogelator and their photocatalytic activities were evaluated by a methylene blue method. The TiO2 nano-networks were formed by which the self-assembled nanofibers of the gelator acted as a template, and their crystal structure was controlled by the calcination temperature. The rutile TiO2 nano-network, which was fabricated at 700 degrees C, showed a good photocatalytic activity.