Authors have experienced a case of polyostotic fibrous dysplasia and the case is reported in this paper with a review of the literature. A 24 year old male, R.O.K. army private, seen at the 3rd Army Hospital in 1966, with multiple bony involvement of ribs, pelvis, both femurs, tibias, left fibula, metatarsal bones, right humerus and radius, which revealed charcteristic "fibro-cystic appearence" and partial sclerotic changes. The blood chemistry showed moderately elevated serum alkaline phosphatase and slightly elevated calcium level. The bone biopsy taken at rib and iliac bone revealed typical appearence of fibrous dysplasia.dysplasia.