[en] Highlights: • Smart aminosilane modified-SnO₂/Porous silica nanocomposite was synthesized. • High efficiency removal of lead ions and bacterial inactivation were obtained. • The maximum adsorption capacity was 653.62 mg g⁻¹. • Nanocomposite possessed exceptional disinfection ability toward E-Coli and S. aureus bacteria. - Abstract: The aim of the present study is to synthesize a new and proficient nanoadsorbent for rapid removal of heavy metals and disinfection of microorganisms. The proposed nanoadsorbent was fabricated using SnO₂ nanoparticles as the core, coated with mesoporous silica and further modified with 3-Aminopropyl triethoxysilane to render SnO₂/PSi/NH₂ nanocomposite. The nanocomposite was characterized using Fourier Transform Infrared (FTIR), X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Nitrogen adsorption-desorption analysis. The potential of the resultant SnO₂/PSi/NH₂ nanocomposite for the convenient removal of Lead ions in a batch systems was investigated as a function of solution pH, contact time, adsorbent dosage, temperature and metal ion concentration. The adsorption behavior was in good agreement with Sips and Langmuir isotherm models. The maximum adsorption capacity of SnO₂/PSi/NH₂ was 653.62 mg g⁻¹. Furthermore, the desorption experiments demonstrated that the proposed nanocomposite could be used frequently for at least three consecutive cycles with minor losses in adsorption performance. The bacterial inactivation ability of SnO₂/PSi/NH₂ toward E-Coli and S. aureus bacteria was also evaluated using disk diffusion and linear cultivation tests, according to which the SnO₂/PSi/NH₂ nanocomposite possessed exceptional disinfection ability toward both bacteria, specifically S. aureus.