This paper reported the deformation characteristics of Al-2.2 wt.%Mg alloy processed by differential speed rolling (DSR) based on microstructure evolution and finite element (FE) analysis. The FE analysis was carried out to examine the distribution of the effective strain during DSR deformation with respect to the roll speed ratio. As the roll speed ratio increased from 1:1 to 1:4 for the lower and upper rolls, the amount of the effective strain imparted to the sample during DSR deformation increased, which was also accompanied with reasonably homogeneous distributions of microstructure and microhardness over the entire samples. At the roll speed ratio of 1:4, the effective strain of ~1.5 was calculated in the top part of the DSR-deformed sample. In addition, the rolling load was observed to decrease with the roll speed ratio increased, which was attributed mainly to the influence of friction between the rolls and sample.