Carbon nanotubes, carbon nanocones, and graphene nanoribbons are carbon-based nanomaterials, and their electronic and field emission properties can be altered by either electron donors or electron acceptors. Among both donors and accepters, nitrogen and boron atoms are typical substitutional dopants for carbon materials. The contribution of this paper mainly provides a comprehensive overview of the theoretical topics. The effect of nitrogen/boron doping on the electronic and field emission properties for carbon nanotubes, carbon nanocones, and graphene nanoribbons is reviewed. It is also suggested that nitrogen is more an n-type donor. The discussion about the mechanism of field emission for N-doped carbon nanotubes and electronic structures of N-doped graphene nanoribbons is interesting and timely.