This chapter is a review of the application of Raman spectroscopy in characterizing the properties of graphene, both exfoliated and synthesized, and graphene-based materials such as graphene-oxide. Graphene is a 2-dimensional honeycomb lattice of sp2-bonded carbon atoms and has received enormous interest because of its host of interesting material properties and technological potentials. Raman spectroscopy (and Raman imaging) has become a powerful, noninvasive method to characterize graphene and related materials. A large amount of information such as disorder, edge and grain boundaries, thickness, doping, strain and thermal conductivity of graphene can be learned from the Raman spectrum and its behavior under varying physical conditions. In particular, this chapter will discuss Raman characterization of graphene with artificial disorder generated by irradiations such as electron-beam exposure and oxygen plasma, focusing on the defect-activated Raman D peak. © 2013 by Nova Science Publishers, Inc. All rights reserved.