Hollow hexagonal fluorapatite (FHAp) nanoprisms have been successfully prepared via a template-free method with the assistance of Na(2)EDTA/citric acid (CA) mixed chelating reagent. These novel hollow FHAp nanoprisms have an outer length of about 1 mu m, an average outer diameter of 150 nm, and a shell thickness of about 50 nm. The effects of reaction temperature and chelating reagent on the formation of final products were Studied. A possible formation mechanism for the hollow FHAp nanoprisms is proposed.