The study for chemical component and structure of salivary calculi is essential to clarify the mechanism of calculi formation and these could be different according to the race and pattern of meals. Twenty-six cases of submaxillary calculi were analyzed for chemical component and structure. Chemical analysis by X-ray diffraction method revealed that major component of calculi was calcium phosphate in 81%(21 patients). Grossly calculi were measured from 2 mm to 29 mm in diameter, their color were white to dark brown, and surface were either smooth or rough. The study for microstructure by microradiographs showed that calculi have lamellar structures with one central core in most cases. The lamellated patterns were less conspicuous toward the central core.