Culture-negative endocarditis accounts for 2.5-31% of all endocarditis cases and remains a diagnostic and therapeutic challenge. Bartonella spp. has only recently been recognized as an important cause of culture-negative endocarditis. We report a case of Bartonella henselae endocarditis occurring in an immunocompetent man who owned a cat and had previously been diagnosed with valvulopathy. Diagnosis was made only after prolonged diagnostic work-up with serology and with PCR and subsequent sequencing to identify the microorganism in the excised valves. The duration of treatment in patients with bartonella endocarditis is not clearly defined, and we decided to treat our patient with a prolonged course of antibiotic. Surgical treatment is usually necessary and was also successful in our patient. To our knowledge, this is the first case of bartonella endocarditis occurring in our geographic area.