We report two cases of periosteal chondroma of the rib, an extremely rare entity. The first case involved a 5-year-old boy who was admitted with pain and swelling around his left fifth rib. Surgery was performed in May 1999, and an 8 x 6 x 5 mm tumor was resected with the fifth rib. The second case involved a 39-year-old man with a 2-month history of cough who was referred to our department after a coin lesion had been detected on a chest roentgenogram. Physical examination on admission did not reveal any pain or tenderness. The rib tumor was resected along with the fourth rib by video-assisted thoracoscopic surgery and minithoracotomy in February 2000. The tumor was well encapsulated and consisted of an elastic hard mass measuring 22 x 15 x 13 mm. Both patients had an uneventful postoperative course and have remained well with no evidence of recurrence. Our review of the literature revealed only six previously documented cases of periosteal chondroma of the rib.