Bartonella henselae, is a gram-negative bacterium which causes cat scratch disease (CSD) in man. There are sporadic case reports of CSD in Turkey. Cats play an important reservoir role for B.henselae transmission to man. In this report, a cat owner with fever of unknown origin was presented. Bartonella spp. was isolated from the blood culture of cat which had chronic progressive gingivostomatitis. B.henselae was identified by amplification of a region of citrate synthase (gltA) gene by using polymerase chain reaction and typed as genotype I by restriction fragment length polymorphism method. Following this identification the cat owner was investigated for the history of CSD and it was learned that he had a history of fever of unknown origin. The investigation of the patient's serum for the presence of specific B.henselae antibodies by immune fluorescence antibody test (Vircell, Spain) revealed B.henselae IgG type antibodies at a titer of 1:128. Gingivostomatitis in cats may act as a reservoir for Bartonella infection. Thus during the evaluation of patients with fever of unknown origin, Bartonella infections should be considered and possible contact with cats/dogs should be investigated.