Objectives: Bioactive compounds from the marine habitat have been always represented as the greatest unexploited source of potentially active pharmaceutical agents. Squid ink, being reported for its various therapeutic applications has not been extensively studied for its bioactive molecules. Thus an attempt has been made in this study to isolate and characterize a novel antimicrobial protein from the ink of Loligo duvauceli. Methods: The fresh squids were decapitated and the ink sac was dissected to collect the ink. Melanin free ink was obtained by ultracentrifugation. The ink was then subjected to SDSPAGE to analyze the proteins present in it and a new protein with a molecular weight of approximately 60 Kda was selected as the target protein. Native PAGE was then performed to isolate the protein in an original form and was eluted using passive gel elution method. The eluted protein was then subjected to an enzyme linked coupled assay for the L-amino oxidase [LAO] activity. The Km and Vmax values for the L-amino acids utilized as substrates for the assay were determined by Lineweaver Burk Plots. The eluted protein was sterilized by syringe filtration after which the antimicrobial potential of the protein was checked by agar well diffusion method against the drug resistant pathogens such as ESBL, MRSA and the pathogenic yeast C.albicans. The MIC value of the protein was determined by Microbroth dilution method. Results: A new protein of approximately 60 Kda was successfully isolated and was characterized to exhibit the L-amino acid oxidase activity. The protein was scored to possess a promising antibacterial and antifungal activity against the test pathogens. The MIC value was determined as 25 __ampersandsignmu;g/ml for ESBL producing strains of E.coli and K.pneumoniae. MIC value for the methicillin resistant S.aureus and C.albicans was deduced as 12.5 __ampersandsignmu;g/ml. This new protein exhibiting a LAO activity was further named as Lolduvin -__ampersandsignnbsp;S. Conclusion: This study was concluded by stating that Lolduvin-S exhibits the LAO activity and had been reported to possess a promising antimicrobial activity against the dreadful drug resistant pathogens. Lolduvin-S could be employed in near future as a novel therapeutic agent to treat various systemic ailments.