The structure and binding energy of copper clusters of the size range 70 to 150 were studied by using the embeddedatom method.The stability of the structure of the clusters was studied by calculating the average binding energy per atom,first difference energy and second difference energy of copper cluster.Most of the copper clusters of the size n=70-150 adopt an icosahedral structure.The results show that the trends are in agreement with theoretic prediction for copper clusters.The most stable structures for copper clusters are found at n=77,90,95,131,139.