Self-diffusion in liquid alloys of Ni-Al and Ti-Al systems, depending on the concentration of the components, as well as in pure metals Al, Ni, and Ti, has been studied using the molecular dynamics method. Knowledge of the diffusion parameters in melts of binary systems, such as Ni-Al and Ti-Al, is necessary for a more detailed understanding and prediction of the processes occurring during combustion synthesis and in the manufacture of wares by melt casting. For the considered systems, self-diffusion characteristics (activation energy and preexponential factor in the corresponding Arrhenius equation) are found separately for atoms of different types. Good agreement of diffusion characteristics with experimental data was obtained for pure metal melts, which indicates the physical realism of the molecular dynamics model and EAM potentials used. In addition to pure metals, three component ratios were considered for each system: A75B25, A50B50 and A25B75. According to the data obtained, the activation energy of diffusion substantially depends on the concentration of the components, and the highest, among the considered compositions, for Ni75Al25 for Ni-Al system and for Ti50Al50 for Ti-Al system. At the same time, no significant predominance of diffusion mobility of atoms of different types was observed for all the mixture compositions considered.