The present invention relates to new antibodies capable of binding specifically to the human CD151 protein, especially monoclonal antibodies of murine origin, which are chimeric and humanized, and also to the amino acid and nucleic sequences coding for those antibodies. The invention also includes use of those antibodies as medicaments for the prophylactic and/or therapeutic treatment of cancers and in diagnostic methods or kits for diseases associated with overexpression of the CD151 protein. Finally, the invention includes products and/or compositions comprising such antibodies in association with antibodies and/or anti-cancer agents or conjugated with toxins and/or radioelements and their use in the prevention and/or treatment of certain cancers.