Glidcop Al-15 is an Oxide Dispersion Strengthened (ODS) copper which has been widely used throughout the world in high-heat-loaded components because of its high strength especially at higher temperatures. At the European Synchrotron Research Facility (ESRF, Grenoble, France) the Glidcop Al-15 is used for manufacturing photon absorbers. It consists in two segments of OFHC (Oxygen-Free High Conductivity) copper brazed with another segment of Glidcop Al-15. This absorber is subjected to intense thermal stress cycles due to the high intensity X-ray beams. This work aims at studying the fatigue behavior of the Glidcop Al-15 at high temperature (300 °C). This study is divided into two parts: First the effect of heat treatment cycles which simulate brazing operation on Glidcop Al-15 will be analyzed. Then the effect of temperature on low cycle fatigue (LCF) behavior and failure mechanisms will be discussed.