N-doped carbon hollow microspheres (NCMs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor and N-dopant and ferrocene as both the catalyst and carbon precursor. It is shown that the size of the NCMs can be tuned just by changing the annealing temperature of the CVD furnace. The atomic percentage of nitrogen doping in NCMs could be achieved to 7.85% without sacrificing the hollow spherical structure. Probable growth mechanism of NCMs was proposed in this paper. The work reported here may pave a way for designing novel various atom-doped carbon microspheres.