Mediterranean spotted fever (MSF) due to Rickettsia (R.) conorii conorii is an acute febrile disease endemic in Italy, where about 400 cases are reported every year, transmitted to humans by the brown dog tick.. However, in recent years other tick-borne Spotted Fever Group rickettsiae have been documented to cause infection in humans in the Mediterranean basin. All of these agents, though causing milder illnesses than R. conorii, crossreact with it thus obliging to interpret with care serological tests. MSF in immunocompetent host is typically characterized by fever, skin rash and a black eschar at the site of the tick bite ('tache noire')In this paper we describe a case of Spotted Fever Rickettsiosis with a benign course in a HIV positive patient.