A latex polymer of styrene-acrylic acid emulsion is used as a template for the synthesis of novel porous nanosilica (PNS) material. TiO2 is dispersed over PNS by solid state dispersion and the composite materials are characterized by XRD, nitrogen adsorption-desorption isotherms, SEM and TEM measurements. The photocatalytic activities of the composite TiO2/PNS catalysts are evaluated for degradation of isoproturon pesticide in water with different parameters under solar light. Furthermore, commercial pesticide solutions containing imidacloprid and phosphamidon were also degraded successfully with the composite system using the same developed conditions for isoproturon degradation. The 5 wt% TiO2/PNS is found to be active in the present investigation. (C) 2009 Elsevier B.V. All rights reserved.