Quantum chemical calculations have been performed for the MCCBr−NCM′ (M and M′ = H, Li, Na, F, NH2, and CH3) halogen-bonded complexes at the MP2/aug-cc-pVTZ level. The binding energy is in a range of 1.34−23.42 kJ/mol. The results show that the alkali metal has a prominent effect on the strength of halogen bond, and this effect is different for the alkali metal in the halogen and electron donors. The alkali atom in the halogen donor makes it weaken greatly, whereas that in the electron donor causes it to enhance greatly. Natural bond orbital analysis shows that the alkali atom is electron-withdrawing in the halogen donor and electron-donating in the electron donor. In formation of the halogen bond, the former is a negative contribution, whereas the latter is a positive one. A similar charge transfer is also found for the H atom in the halogen and electron donors. These complexes have also been analyzed with the atoms in molecules theory.