Abstract: Objective:To analyze the X-ray plain film and CT image of symptomatic accessory navicular bone.Methods:Twenty-eight cases (32 feet) of symptomatic accessory navicular bone which had been confirmed by clinical presentation,X-ray plain film and CT were taken routine orthotopic and oblique X-ray plain film.The pictures of both feet of 12 cases were compared and 20 cases were performed coronal CT routine scan.Results:Twenty-four feet presented soft tissue swelling,19 feet sclerosis and hyperplasia of accessory navicular bone,9 feet cystic degeneration of accessory navicular bone and 3 feet fragmentation of accessory navicular bone;Sclerosis and hyperplasia of navicular bone were observed in 13 feet,integration of navicular bone and accessory navicular bone in 4 feet.Three feet showed widened distance between navicular bone and accessory navicular bone,and 2 feet navicular bone hypertrophy.Conclusions:The symptomatic accessory navicular bone can be diagnosed by X-ray plain film and typical clinical presentation.CT routine scan image has great supplementary value.