This paper describes the synthesis of TiO2 nanoparticles by laser ablation in solution synthesis (Lasis). The laser excimer beam passes through a focusing lens and it is sent to the reaction chamber. The frequency used during the synthesis was 20 Hz, intensity 26 kV The metal ablated by the laser beam undergoes an oxidation process resulting from the reaction with water. We obtain TiO2 nanoparticles with average size of 6.5 nm, crystallized in the rutile structure. The crystallographic and morphological structure was studied by transmission electron microscopy. (C) 2011 Elsevier B.V. All rights reserved.