Surface Plasmon Resonance was explored as optical transduction technique for monitoring the response of nano-rods and nano-dots based TiO2 thin films as sensing layers for alcohol vapours. Organic solutions of surfactant-capped TiO2 nanoparticles were prepared by means of a colloidal chemistry route, and used as precursors for depositing the sensing layer onto Au/glass substrates. The sensing properties of the active material were examined in relation to the colloidal nanocrystal synthesis, the nanoparticle shape and the morphological features of both as-deposited and thermally annealed films and to the presence of the organic passivating shell on the TiO2 nanocrystals surface.