A semiconductor memory device and a method of manufacturing the semiconductor memory device, in which a bit line can have a low resistance without an increase in the thickness of the bit line. In the semiconductor memory device, an insulating layer having a contact hole that exposes a conductive region is formed on a semiconductor substrate having the conductive region. A barrier metal layer is formed along the surface of the insulating layer and the surface of the contact hole. A grain control layer is formed between the barrier metal layer and the tungsten layer. A tungsten layer is formed on the grain control layer. A grain size of the tungsten layer is increased by the grain control layer.