In this paper, a KrF excimer laser is used to decompose 4H-SiC substrates to prepare graphene layers. The research is focused on the influence of the crystal orientation of 4H-SiC on the quality of the graphene produced. The effects of laser energy density, pulse number, and crystal orientation on graphene quality are analyzed. With a laser energy density of 1.06 J/cm 2 and a pulse number of 8000 shots, the graphene obtained on the polar Si-plane (0001) and on the non-polar a-plane (11?20) of the 4H-SiC sample are both of the best quality. We find that a buffer layer that provides a template for the growth of graphene is formed between Si-plane (0001) and 4H-SiC substrate. The graphene obtained from the buffer layer is consequently more ordered and has fewer defects. In contrast, there is no buffer layer between the photo-generated graphene on a-plane (11?20) and 4H-SiC substrate, which results in the generated graphene being disordered and more sensitive to the laser parameters.