The aim of this study is to describe 2 ectopic localizations of Carabelli's tubercle. Carabelli's tubercle or cusp is present, in a fair number of cases, in the vestibular walls of both first upper molars. Its size may vary. It is named after the Italian scientist Antonio Carabelli who first had described it in the first half of the 19(th) century. Carabelli's cusp has been often detected and studied in not hybridized ethnical groups, especially Eastern and Central Ameri-can groups, in which the evaluation of heritability and sex distribution is easier. It has been found that this cusp is not clinically important, it may only sometimes interfere with orthodontic treatments. It is seldom present in the second upper molars and almost never in the vestibular walls of either side of the second upper or lower molars. After a review of the literature showing that this cusp is more rarely present in Caucasian peoples, the authors describe 2 case reports with ectopic localization. This has never been found in recent literature and therefore it is to be considered absolutely rare.