The Authors describe a rare case of Yersinia Enterocolitica (Y.E.) infection in a child affected by thalassemia. The onset of the disease was that of an acute enteritis with diarrhea, fever, vomiting and abdominal pain which subsequently evolved in a picture consistent with an acute appendicitis. Laparotomy was then performed and showed a marked suppurative mesenterial lymphadenitis with mild appendicular inflammation and Y.E. infection was suspected. Culture from lymphonodes confirmed the presence of Y.E. sensitive to tobramicin and CTM. The use of these chemiotherapic agents has been followed by a rapid clinical improvement. Our recent experience could suggest some practical considerations: 1) Culture of Y.E. should be routinely performed in all children affected by acute gastroenteritis and particularly in those, above 5 years of age, in which the infection can simulate acute appendicitis. 2) Special attention should be carried out in children affected by thalassemia who can easily present more serious disease often complicated by septicemia. 3) Therapy depends on the form and severity of the disease and should be always guided by in vitro sensitivity test because of the possibility of resistence of Y.E. against the most frequently used antibiotics in septicemia.