Helicobacter cinaedi, a gram-negative spiral bacillus that inhabits the intestinal tracts of rodents and primates, is associated with gastroenteritis in humans. H. cinaedi infection has been commonly reported in immunocompromised individuals such as human immunodeficiency virus-infected patients, but rarely in immunocompetent individuals. Prior contact with animals has attracted attention as a possible source of H. cinaedi infection. We report a case of meningitis in an immunocompetent 34-year-old woman who had daily contact with a kitten for a month. She developed acute headaches, fevers, and chills. Neurological examination revealed neck stiffness and her cerebrospinal fluid (CSF) exhibited polymorphonuclear pleocytosis and a decreased concentration of glucose. Blood and CSF cultures were negative; however, the pathogen responsible for her condition was identified as H. cinaedi by polymerase chain reaction in CSF. This is the first adult case of meningitis caused by H. cinaedi. Thus, this bacillus should be considered a possible causative agent of bacterial meningitis in healthy adults.