The study of antimicrobial peptides is a rapidly growing field. Antibacterial peptides were first considered rather species-specific. Therefore, we focused our review of peptide antibiotics, although the peptide antibiotics are composed of amino acids, they often show little similarity to gene-encoded polypeptides in terms of structure and mechanism of their biosynthesis. Alternatively, an extensive reference survey was conducted for the peptides used as antibiotics, and some examples of antibiotics that are chemically composed of various amino acids and peptides were studied. Moreover, we focused in this review some selected examples of important peptide antibiotics, for example, bacitracin (I), gramicidin (II), monamycins, alafosfalin and albomycisn.