Recently materials containing azo units have gained wide interest and represent promising candidates for photoactive materials due to their properties, including optical storage capacity, optical switching, holography, large second-order nonlinearity and high-speed response. A promising approach in the fabrication of new materials containing azo units for second-order nonlinear optics is sol-gel technique. We report here on the sol-gel synthesis of SiO2-P2O5 films doped with some pyrazolone compounds. Tetraethylorthosilicate (TEOS) and phosphoric acid (H3PO4) were used as precursors and the organic compound was added under continuous stirring in the precursors‟ mixture. The structure of the deposited azo-derivatives doped thin films was examined by Fourier Transform Infrared and Raman spectroscopy and their optical properties by UV-VIS spectroscopy. The nonlinear optical efficiencies due to the interaction of the NLO-active chromophores with the inorganic matrix was measured using a femtosecond Ti:sapphire laser. The properties of the films were investigated and correlated with the thermal treatment temperature.