Abstract: Objective To establish a new method to estimate injury-tool by analyzing the components of left metal particles from hammers impact on pig skin and filter paper using scanning electron microscope and energy dispersive X-ray spectrometer （SEM-EDX）. Methods The pig skin and filter paper were stricken by two steel hammers. The left metal particles were examined by SEM-EDX and the results were statistically analyzed by SPSS 13.0. Results The characteristics of left particles showed stable by several impacts using one steel hammer. The left particles showed no statistical difference for impact on pig skin and filter paper. The left particles displayed a statistical difference using two hammer with different components. Conclusion SEM-EDX can be used to detect the left metal particles from the steel hammer and can provide a method for estimating injury-tool.

Key words: forensic pathology, wounds and injuries, metals, scanning electron microscope and energy dispersive X-ray spectrometer, skin