Study of grain refinement has developed to improving the mechanical properties of low carbon steel. Wedge shaped slab of low carbon steel were deformed through warm rolling methods of 500, 550, and 600oC to produce a finer ferrite grains. The thickness reduction of deformation is 80, 75, 67 and 50% .Dynamic recrystallizations were confirmed at warm working temperature in this study. Grains size which obtained through this process could improve the hardness and its mechanical properties and also its performance in corrosive environment. The smallest grain size was obtain from 80% deformation is 5.2 µm and the tensile strength is 817.65 MPa. Its gives the evidence that warm rolling can use to produce the fine grain at warm temperature of 600oC.