Antimicrobial peptides (AMPs) are host defense peptides that are well conserved throughout the course of evolution. Histones are classical DNA-binding proteins, rich in cationic amino acids, and recently appreciated as precursors for various histone-derived AMPs. The present study deals with identification of the potential antimicrobial peptide sequence of teleostin from the histone H2A of marine teleost fishes, Cynoglossus semifasciatus and Tachysurus jella. A 245 bp amplicon coding for 81 amino acids was obtained from the cDNA transcripts of these fishes. The first 52 amino acids from the N terminal of the peptide were identical to previously characterized histone-derived antimicrobial peptides. Molecular and physicochemical characterizations of the sequence were found to be in agreement with previously reported histone H2A-derived AMPs, suggesting the possible role of histone H2A in innate defense mechanism in fishes.