Abstract: The electric explosive method has the advantages of simple operation and mass production to make nano metal particles. The changes of the copper wore in the electrical explosion process are analyzed, and the changes can be divided into the states of solid, liquid, gas and plasma. The relationships between the size, size distribution and composition of nano copper particle, and the explosion energy, copper wire diameter and the length of copper wire are studied. The particle size uniformity is defined, and the distribution of the nanoparticle size is analyzed based on the comparing analysis in the average diameter size and the particle size uniformity. The corresponding experimental researches are carried out, and the analysis and the test of the produced nanometer copper powder are completed by the X-ray diffraction (XRD) and transmission electron microscopy (TEM).