The tensile and fatigue behavior of nanoscale copper at various temperatures has been analyzed using molecular dynamics simulation. The stress-strain curve for nanoscale copper was obtained first and then the Young's modulus of the material was determined. The modulus was larger than that obtained by previous studies and decreased with increasing temperature. From the fatigue test, the cyclic stress-number of cycles curve was obtained and the stress increased with increasing temperature. Furthermore, the ductile fracture configuration was observed in the fatigue testing process under the lower applied stress. It was also observed that nanoscale copper appears to have a fatigue limit of 10(5) cycles. (C) 2003 Published by Elsevier Science Ltd.