Abstract:The deformation structure of single crystal copper during 4 passes equal channel angular pressing (ECAP) througth route Bc were investigated by electron backscatter diffraction (EBSD) and XRD methods, and the mechanical properties of the deformed material were measured. The results show that the macroscopic orientation of single crystal under low pass deformation was not changed. After 2 passes，orientation-ordered shear bands appeared and inclined at angles in the range of 15°–20°from the ED direction，deformation texture {111}<112> appeared on grains；After 4 passes，the angle between the shear band and the ED direction was constant , the inclined direction was opposite to that of the 2 passes，the texture of the material was still in texture of {111}<112>，and large angle grain boundary was not presented；The tensile strength increased from 168MPa to 395MPa, the elongation decreased from 63% to 26.5%, the material hardness increased from 60Hv to 125Hv and then was tended to be changed little. Because of dislocation accumulation, the plastic deformation capability of the material becomes worse and the necking area increases. ECAP has positive effect on enhanceing the strength of single crystal copper with not broken grains.