In the present study, the effect of the Reynolds number on the incompressible turbulent channel flow is investigated by means of the direct numerical simulation. In the large Reynolds number case, the turbulence energy, Reynolds shear stress and bulk mean velocity increase and the anisotropy of the Reynolds normal stresses near the wall is weakened in comparison with the low Reynolds number one. The large-scale structures appear in the visualization result of the large Reynolds number flow and this behavior corresponds to the dependency of the length scales obtained from the two-point correlation on the Reynolds number.