Recently, remarkable advances in the mechanistic understanding of Ni-catalyzed amide C-N bond activation have been achieved by computational chemists. These computational studies revealed the key mechanistic processes of Ni-catalyzed amide C-N bond cleavage, providing the molecular basis for the rationalization of reactivities and selectivities. This review summarizes the general mechanistic models of Ni-catalyzed amide C-N bond activation, and discusses their applications in the understanding and design of Ni-catalyzed cross coupling reactions involving amides.