Abstract: Graphene, a one-atom-thick sheet of carbon atoms, is a material that is attracting hot interest in condensed matter physics. The properties of graphene are highly sensitive to atomic structure and surface morphology, so the structure is of basic importance. In this paper we will review transmission electron microscopy (TEM) studies on graphene′s structure, including the layer numbers, stacking, orientation and surface morphology. Studies on the surface defects, atomic edges and adatoms by high-resolution TEM imaging will also be described.