Ion implantation of Aluminum is a useful technique to improve hardness and tribological properties. This paper reports on a comparative study of modifications produced by Nitrogen implantations on three different Al commercial alloys. Different Nitrogen doses have been implanted, hardness and wear tests have been carried out to investigate the influence of implantation parameters. Tribological changes are referred to implantation dose and to thermal post-treatments, as well as to testing conditions. Applications are relevant in aeronautical and moulding sectors.