Bentonite (bent) clay supported silver (Ag)ititanium dioxide (TiO2) nanocomposite material was green synthesized by facile thermal decomposition method in the absence of reducing and precipitating agents. The samples were characterized by XRD, BET, HR-SEM with EDX mapping, TEM with SAED patterns, XPS, PSA, FT-IR, and UV-Vis DRS. XRD and EDX spectra showed peaks of Ag and TiO2, confirming the formation of the Ag/TiO2 nanoparticles in the composite. TEM revealed the uniform distribution of Ag/TiO2 nanoparticles cluster on the surface of the bent with an average size of similar to 5 to 50 nm. The antibacterial activities of Na-bent, Ag, TiO2, and Ag/TiO2/bent nanocomposite samples were tested against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E.coli) bacteria by the well diffusion method. Furthermore, the cytotoxicity of Ag/TiO2/bent nanocomposite material was determined by 3-111,5-dimethylthiazol-2-y11-2,5-diphenyltetrazolium bromide (MTT) assay. Also, the succinatede-hydrogenase release showed the nontoxic nature of the nanocomposite at low concentrations. The cytotoxicity results of samples were evaluated using human embryonic kidney cell line (HEK 293) and have given excellent biocompatibility and cell proliferation in the in vitro studies. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.