Nitrogen-doped (N-doped) graphene has attracted increasing attentions because of the significantly enhanced properties in physic, chemistry, biology and material science, as compared with those of pristine graphene. By date, N-doped graphene has opened up an exciting new field in the science and technology of two-dimensional materials. From the viewpoints of chemistry and materials, this article presents an overview on the recent progress of N-doped graphene, including the typical synthesis methods, characterization techniques, and various applications in energy fields. The challenges and perspective of N-doped graphene are also discussed. We expect that this review will provide new insights into the further development and practical applications of N-doped graphene.