The titanium silicalite-1 (TS-1) has been used to oxidize aniline with H2O2. Under the working conditions, nitrosobenzene and azoxybenzene were the major products formed. The H2O2 efficiency and the product selectivities largely depended on the experimental parameters, particularly the temperature, the catalyst concentration and the nature of the solvent. The aniline conversion and the product distributions were also affected by the morphology of the catalyst, suggesting that some of the reaction steps were limited by the diffusion within the pores.