Simple aqueous solution-based chemical methods have been developed for the synthesis of Ag/AgCl nanoparticle-mesoporous silica nanocomposites. Ag loading in the mesoporous silica was accomplished using a wet-impregnation method. The AgCl-mesoporous silica nanocomposite material(AgCl-mSi) was synthesized by using a ’one pot’ method. Synthesized materials were characterized using X-ray diffraction,N2 adsorption-desorption analysis and high-resolution transmission electron microscopy. Antibacterial activity of the synthesized materials was investigated against Escherichia coli(E. coli) using the conventional plate-count method. All the materials showed high antibacterial activity even when the percentage loading of Ag in the nanocomposite was as low as 10 wt%. Simple aqueous solution-based chemical methods have been developed for the synthesis of Ag / AgCl nanoparticle-mesoporous silica nanocomposites. Ag loading in the mesoporous silica was accomplished using a wet-impregnation method. The AgCl- mesoporous silica nanocomposite material (AgCl-mSi) was synthesized by using a ’one pot’ method. Synthesized materials were characterized using X-ray diffraction, N2 adsorption-desorption analysis and high-resolution transmission electron microscopy. Antibacterial activity of the synthesized materials was investigated against Escherichia coli (E. coli) using the conventional plate-count method. All the materials showed high antibacterial activity even when the percentage loading of Ag in the nanocomposite was as low as 10 wt%.