Dynamic recrystallization (DRX) at triple junction in copper tricrystal was investigated during high-temperature tensile deformation. DRX nucleation occurred preferentially at triple junction at lower strain than the peak strain (about 2/3). Preferential occurrence of DRX nucleation at triple junction is considered as a result of stress and deformation concentration. Most of DRX grains were twin. DRX nucleation process at the triple function was discussed in relation to grain-boundary sliding, fold formation and grain-boundary migration.