The spinodal decomposition of a two-dimensional model binary fluid undergoing planar Couette flow has been studied by molecular dynamics simulation. The effect of the strength of the shear field on the growth of the domains was analyzed. The main effect of the shear field is the deformation of the domains which results in anisotropic structure developments. We have characterized these anisotropic structures by measuring the domain size in two different directions, the direction of the flow and the direction of the shear. We find that the dependence of the deformation of the domains on the strain applied to the system shows the same behavior as found in experiments. Moreover, we find that the shear flow can enhance the domain growth in the direction of the flow and it can restrain and even suppress this growth in the direction normal to the flow. The influence of the morphology on rheological properties was also analyzed. We find that viscosity depends on the quench time and the shear field, and is caused by the extension and direction of the interfacial area.