The mineralization of the psammoma body has a high specificity in diagnosing papillary thyroid carcinoma, and an analysis of its mineral composition may provide some support information on the origin and development of the disease. Focusing on the concentric lamellated calcified bodies in papillary thyroid carcinoma, the authors used ESEM, EDAX, EPMA, FTIR and HRTEM to investigate the morphology, structure and mineral composition of the sample. The results show that the concentric lamellated structure has genetic characteristics of micromicellae, and that the psammoma bodies are composed of nano_size carbon hydroxyapatite and some amorphous calcium phosphates with relatively low values of Ca/P（At%）. The Ca, P and Ca/P（At%）in the psammoma body have an increasing tendency inwards.