Cat scratch disease (CSD) is an uncommon condition. When a patient is infected, the disease is often self-limiting. Cat scratch disease involving the musculoskeletal system had been described, but the manifestation of the disease in hand remained unexplored. We report a case of chronic flexor tenosynovitis of the left index finger caused by cat scratch disease. In this case, the antibiotic treatment did not improve the clinical outcome. However, surgical debridement of the diseased finger resulted in a tremendous improvement in terms of pain and range of motion.