Introduction: The immune depressed patients are at increased risk of developing Streptococcus gallolyticus endocarditis. Streptococcus gallolyticus is a normal inhabitant of the human gastrointestinal tract and the exact reason why it suddenly becomes invasive is not known. The infection is easily controlled by antibiotics, but a valvular replacement may be needed for gross valvular dysfunction, embolization or severe heart failure. Some patients may have associated colonic or hepatic lesions needing surgical intervention that increase morbidity, mortality and costs. Methods: We describe a 55 year old diabetic patient with spontaneous Streptococcus gallolyticus endocarditis on native valves. The patient was a non drug abuser and had no previous history of rheumatic or acquired valvular heart disease. He had no recent dental or other invasive bleeding procedures. Echocardiography showed aortic valve vegetation and the blood cultures were positive for Streptococcus gallolyticus. Intra-venous antibiotic therapy was started. Results: Two weeks following the institution of therapy, the patient developed acute ischemia in the left leg, by embolization with a fragment of the aortic valve vegetation. Embolectomy was performed with a Fogarty arterial catheter. Emergency open heart surgery was necessary and replacement of the aortic valve with a mechanical prosthesis was performed. Antibiotherapy was continued, with a good outocome and a complete recovery of the patient. Conclusions: In conclusion, the presented case informs the physicians about the risk of spontaneous infective endocarditis in non drug addicted patients, without a history of congenital or acquired valvular heart disease. Immune-depression, as well as nutritional habits such as frequent consumption of uncooked meat and fresh milk products, might have an impact on S. gallolyticus intestinal colonization and subsequent bacteremia and IE.