In this study, the antibacterial cotton fabric was prepared using zinc oxide/silicon dioxide (ZnO/SiO2) nanocomposite. The ZnO nanoparticles were synthesized with an in situ approach using two different methods on the cotton fabric. One of the methods was to synthesize ZnO nanoparticles into the prepared sol solution, and then coating on the cotton fabric. The other method was to synthesize ZnO nanoparticles on the silicon dioxide-coated cotton fabric. The morphological, structural, thermal, and antibacterial properties of ZnO/SiO2 nanocomposite-coated cotton fabric was studied using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffractometer, thermo gravimetric analysis, and Attenuated Total Reflection-Fourier Transform Infrared spectrometer. Synthesis of ZnO nanoparticles on the silicon dioxide coated cotton fabric sample resulted in agglomerated nanoparticles on the surface of cotton fiber, while the spherical nanoparticles structure was formed by synthesizing them into the sol solution of silicon dioxide. The EDS results indicated presence of ZnO/SiO2 nanocomposite on the surface of coated cotton fabric, and presented an inhibition zone against Staphylococcus aureus and Escherichia coli. (C) 2014 Elsevier B.V. All rights reserved.