Antibacterial peptides and their multimeric analogues, with a wide range ofaction and low haemolytic activity are described. In particular, the peptidemolecules exhibit a high antimicrobial activity against numerous bacterialspecies, with reduced cytotoxicity and a low haemolysis rate. The molecules ofthe invention are advantageously usable as therapeutic agents and coadjutantsagainst infections caused by strains that are resistant to common antibiotics.