A 10-year-old girl presented with a 2-month history of intermittent fever and palpable masses in the right side of the neck. Whole body FDG PET/CT imaging was performed, showing multiple FDG-avid nodular masses in cervical and abdominal lymph nodes. The patient then underwent excision biopsy of the enlarged right cervical nymph nodes, which confirmed the diagnosis of Kikuchi disease. After steroid therapy, fever and cervical lymphadenopathy subsided. After 3 months, follow up FDG PET/CT was done, and there was no abnormality. Kikuchi disease could lead to the wrong initial diagnosis of tuberculosis or even malignant lymphoma.