American Cutaneous Leishmaniasis (ACL) is an infectious, non-contagious disease caused by a genus Leishmania Protozoa, which affects the skin and the mucosae. Man is infected by bites of phlebotominea and the disease presents mostly as a single ulcerated lesion. The confirmation of the case of ACL is performed by clinical, epidemiological and laboratory diagnosis. We report three cases of autochthonous ACL diagnosed in 2002 and 2003 in the city of Porto Alegre. We show the need to watch out for new cases and to perform environmental control, since, according to the records of the Brazilian Ministry of Health, during the 1997-1999 period, Rio Grande do Sul did not present autochthonous cases of ACL.