In order to conserve a bronze mirror from Wei and Jin Dynasties unearthed at the Fo - Ye Temple in Dunhuang, the decay and damage characteristic of the mirror were described and the main corrosion products were analyzed. First, a picture showing the decay and damage of the object was drawn. Then the composition of the material in the mirror and the mirrors decoration and its main corrosion sites were analyzed by qualitative analysis of wet on bronze mirror, X - ray fluorescence, X - ray inspection, Raman spectroscopy, X - ray diffraction and differential scanning calorimetry The results showed that the bronze mirror was an alloy of bronze, containing both tin and lead; the back of the bronze mirror was found to be covered with an exquisite dragon pattern; the corrosion products of bronze mirror contained copper chloride. These results were used to develop a scientific conservation plan.