Nanotechnology is the emerging modern research gained more attention in the field of Biotechnology. In the present research, total of six endophytic fungi such as Aspergillus fumigatus, Cladosporium cladosporioides, Colletrotrichum Sp, Fusarium oxysporum, and Phomopsis Sp were isolated from the healthy leaves and stem of Mentha arvensis L.and Psidium guajava L. and screened for the production of silver nano particles. The presence of silver nano particles formation was confirmed by the change of color in the fungal extracts and further confirmed by UV-Vis spectroscopy. Furthermore the antimicrobial activity of the silver nano particles was studied by disc diffusion method against Escherichia coli, Salmonella typhi, Klebsiella pneumonia and Staphylococcus aureus. This result will pay the way to use these silver nanoparticles for the treatment of fungal infections.