AbstractTo investigate the neutron irradiation effects for plasma facing components, high heat load test of the CFC/DSCu mockups, irradiated with 0.3 and 0.4 dpa at 300 °C, were carried out in a hot cell by using an electron beam facility. The surface temperatures of the un-irradiated, 0.3 and 0.4 dpa mockups at 5 MW/m2 were about 300, 700 and 1200 °C, respectively. Surface temperatures of the irradiated mockups was increased by the degradation of CFC's thermal conductivity caused by neutron irradiation. No damage could be observed in the mockups up to 1000 cycles×10 s at 5 MW/m2 in this thermal cycle test.