The sheet of pure Al (99.99%) single crystal having (1 12) orientation was deformed up to equivalent strain of 6.4 by the accumulative roll-bonding (ARB) process. The microstructures and orientation of the single crystal ARB-processed by various cycles were characterized by the EBSP measurement. After 1cycle-ARB process, the crystal was macroscopically subdivided into two matrices (macroscopic grain subdivision). These matrices exhibits two different variants of brass orientation, which are (1 01) and (011). In addition to the macroscopic grain subdivision, microscopic grain subdivision also occurred within the matrix to form an ultrafine grained structure in the single crystal specimen after high strains.