Secondary metabolites produced from marine fungi showed promising roles in Biomedical applications. This study aimed to exhibit the Anti-Microbial efficacy of the potent fungal strain Aspergillus terreus JMDL-20. Aspergillus terreus JMDL-20 was isolated from Velankanni Beach, South Coast of Tamil Nadu, India and subjected to Anti-Microbial, Myco-chemical and nanoparticle screening. Morphological and Molecular identification was done for the potent fungal strain. Antioxidant activity and growth curve were studied. Characterisation of Aspergillus terreus JMDL-20 was done by using HPLC and FTIR analysis. A total of twenty-five fungal cultures were isolated. Based on Antimicrobial and Myco-chemical screening of bioactive metabolites, potent fungal strain, JMDL-20 is selected and molecularly identified as Aspergillus terreus. Extracellular Cadmium Biogenic Nanoparticle was synthesized. The Antioxidant activity (%) was found to be 42.8357. Maximum production of secondary metabolites was observed at 16 days. In HPLC analysis, the extracellular compound Lovastatin was identified. FTIR analysis exhibited 31 absorption peaks. Fungal crude metabolite extract and cell-free filtrate of Aspergillus terreus JMDL-20 exhibited a wide range of Anti-Microbial activity.