Nanotechnology is a burgeoning field that plays a very prominent role in the biomedical applications. Among metallic nanoparticles, Silica nanoparticle has gained core attention in nanotechnology owing to its tunable size, shape, porosity, biocompatibility and unique properties. These silica nanoparticles are used in the field of diagnostics, theranostics and treatments. The conventional procedures used in nanoparticle production are extremely hazardous since they entail using hazardous substances, high temperatures, and expensive equipment. As a result, adopting environmentally friendly methods of nanoparticle fabrication has become critical. The green approach of nanoparticles synthesis uses biological entities, ambient parameters and easy downstream processing modalities. Urinary tract infection is a microbial infection that occurs in the urinary tract which is a major concern among women and children. One of the solutions in treating Urinary tract infections is antibiotics which in repeated use leads to antimicrobial resistance and unnecessary side effects. Other alternatives are still in the infancy stage, therefore preferring the use of nanoparticles will be able to overcome the disadvantages faced by antibiotics. The present research investigated the green synthesis of silica nanoparticles with the bioleaching of fungi Fusarium oxysporum from wilted banana pseudo stem and fly ash used in the cement industry. The silica nanoparticles were further characterized by Transmission Emission Microscopy (TEM) and Ultra Violet Visible spectroscopy (UV-Vis). Furthermore, antimicrobial activity of silica nanoparticles was evaluated against UTI causing pathogens Gram positive bacteria (Enterococcus faecalis and Staphylococcus aureus), Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae) and fungal strains (Aspergillus flavus and Candida albicans)through Agar well diffusion test.The toxicity of these nanoparticles would also be a worry; from medical therapeutics to commercial sectors, these particles would need to be created more sustainably to avoid toxicity that might affect everyone's lives. In vitro toxicity evaluation of the biocompatibility of the nanoparticles with blood components are a necessary part of early preclinical development. The purpose of this study is to green synthesize silica nanoparticles from the fungal species Fusarium oxysporum and to characterize the bio transformed silica composites by XRD and FTIR to determine their size. This study also aims at performing the in-vitro toxicity evaluation by chromosomal aberration assay and hemolytic assay and asses the antimicrobial activity of the bio synthesized silica nanoparticle.