An enzyme-free glucose sensor developed based on silver nanoparticles (Ag NPs) via bio-mediated route using Ocimum tenuiflorum leaves extract. The Ag NPs were characterized by X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Particle size analyzer (PSA), Scanning electron microscopy (SEM), Energy-dispersive X-ray (EDAX) spectroscopy, and Transmission electron microscopy (TEM), to study structural, optical and morphological properties. The electrocatalytic activity of Ag NPs towards the oxidation of glucose in the 0.1 M NaOH electrolyte solution was analyzed. The Ag NPs was coated on Glassy carbon electrode (GCE) and reports indicating the outstanding capability such as high sensitivity (895.8 mu AmM(-1)cm(-2)), linear range (1-8.9 mM), response time (< 4s), low detection limit (0.0048 mu M, S/N = 3), long-term stability, reproducibility, repeatability, and selectivity of the sensor. Therefore, the bio-synthesized Ag NPs can markedly helpful to fabricate non-enzymatic, sustainable, simple, low cost, and eco-friendly glucose monitoring devices.