The crystal plasticity finite element method (CPFEM), which incorporates the crystal plasticity constitutive law into the finite element method, has been used to investigate the rolling processes of the cubic oriented Al single crystal. The developed model has been validated by comparison with the experimental observations. The simulation results have shown that after rolling the crystal predominantly rotates around the transverse direction (TD). The rotations around the rolling direction (RD) and the normal direction (ND) are negligible. There are two big deformation bands parallel to the RD in the half thickness of the rolled specimens. Some small bands exist in the big band for high reduction or/and high friction. The effects of reduction and friction on the crystal rotation angle around the TD (θTD) have been discussed in detail. The reduction has a significant influence on θTD. The magnitude of θTD is increased with increasing reduction. Comparing to reduction, the influence of friction is secondary. It only affects the region near the specimen surface.