Spin polarized first principles calculations have been performed to study the structural and electronic properties, and spin coupling of the MnN deposit on the CrN (001) surface. Results indicate that Mn may transform from a paramagnetic to a ferromagnetic system, when adsorbed on a surface. Also, the first CrN layer switches from antiferromagnetic to ferromagnetic alignment. Surface formation energies show that epitaxial growth of θ-MnN on the CrN (001)-(1x1) surface is favorable for N-rich conditions and intermediate conditions. The double MnN layer exhibits an antiferromagnetic behavior, with the magnetic moments coupled parallel and alternating along c. Moreover, the exchange bias effect is manifested in the first CrN layer. The calculated projected densities of states spectra show a half metallic character in the first CrN layer. The Mn magnetic moments are in the range of 2.8–3.3 μB. This work identifies an antiferromagnetic system for possible applications in spintronics.