Biogenic synthesis of silver nanoparticles (AgNPs) using plants has become a promising substitute to the conventional chemical synthesis method. However, the desired size and form of NPs can be produced by optimising the microbe-mediated synthesis by changing their reaction conditions. AgNPs are manufactured by a variety of chemical and physical processes. But so far, these techniques are costly and harmful to the environment. The study here elaborates on the potential of biologically synthesized silver nanoparticles of fungal extract samples from Western Ghats of Agumbe region, Karnataka. In this study, we report the low-cost microorganisms based “eco-friendly” efficient synthesis of silver nanoparticles by using the metal-tolerant fungi Aspergillus niger. On the other hand, the appearance of white precipitate at the end of incubation time confirms the production of AgNPs. The physicochemical characterization of silver nanoparticles was performed by employing, SEM, XRD, and FTIR to investigate the stability and structure of AgNPs. SEM result revealed that the particles were irregular spherical, granules. In addition, FTIR confirms the functional group of the silver oxide nanoparticle. The XRD pattern of synthesized nanoparticles confirms the diffraction peaks of AgNPs at 2θ = 31.82°, 34.51°, 36.27°, 47.71°, 56.76°, 62.95°,66.53°, 68.12°, 69.13°, 72.45°, and 77.09°can be assigned to (100), (002), (101), (102), (110), (103), (200), (201), (004) and (202). Indeed, nanotechnology based microbiological active molecules develops new opportunities for us to explore novel applications in terms of green technology.