Abstract: In nanotechnology, nanoparticles have terrific application in biomedicine due to its novel properties and its eco-friendly nature. The present study reports a facile biosynthesis of silver nanoparticles from the rind extract of Garcinia mangostana, a medicinal plant which acts as a reducing agent. The Surface Plasmon Resonance (SPR) of the silver nanoparticles was characterized using UV-V is spectrophotometer and observed at 460 nm. The nanoparticles were found as spherical and the particle size ranges from 30-40 nm from the Scanning Electron microscopy. The XRD data (X-ray diffraction) shows the crystalline nature and the presence of elemental silver in the synthesized nanoparticles were observed using EDX (Energy dispersive X-ray spectrophotometer) analysis. The interaction of nanoparticles with the extract of G. mangostana was carried out by FT-IR (Fourier Transform Infra red spectroscopy). Various compounds in the rind extract were identified by Thin Layer Chromatography (TLC). Using High Performance Liquid Chromatography (HPLC), the percentage of the compound was analyzed. Then the total number of compounds in methanolic extract of the rind and the molecular weight of particular compound were carried out by Gas Chromatography-Mass Spectroscopy (GC-MS). Finally, the activity of crude extract and synthesized nanoparticles was tested against the human pathogens E. coli, Bacillus subtilis and Aspergillus niger. Various concentrations of the nanoparticle in colloidal form were used to analyze the activity starting from 20 μL for bacteria and 100 μL for fungi. The silver nanoparticle of the rind extract of Garcinia mangostana exhibited strong bactericidal and fungicidal activity which was observed by clear zone of inhibition and it has wide application in the field of medicine.