Cardiobacterium hominis remains an unusual cause of endocarditis, accounting for 0.1% of cases. This slow-growing Gram-negative bacillus belonging to the Haemophilus-Actinobacillus-Cardiobacterium-Eikenella-Capnocytophaga-Kingella (HACECK) group is difficult to diagnose, We describe a new case of endocarditis due to Cardiobacterium hominis and report a special feature that is the rapidity of the diagnosis of this endocarditis caused by this rod associating modern techniques in microbiology (automated blood culture system) and in cardiology (transesophageal echocardiography).