TiO2 nanosized clusters have been prepared by the Langmuir-Blodgett technique starting from the n-octadecylamine-titanyl oxalate complex. The floating film morphology has also been investigated by Brewster angle microscopy (BAM). The presence of TiO2 in the subphase promotes the formation of aggregates of n-octadecylamine on the subphase surface. LB films initially contain TiO2 nanosized clusters embedded in the organic amorphous matrix; their structural evolution induced by thermal annealing has been investigated. UV-vis spectroscopy, high-resolution transmission electron microscopy (HRTEM), and small area electron diffraction (SAD) characterization methods are used as synergic techniques giving complementary information regarding both structural features and photophysical properties.