The vacancies and antisites at InAlAs/InGaAs hetero-interface have been investigated by first-principles calculation based on hybrid density functional (HSE06). We propose an approach to obtain the chemical potentials based on the growth process of hetero-junction. The valence-band maximum of hetero-interface supercell is aligned with the reference of the average electrostatic potential of bulk material. The VIn, VGa, and VAl defects are deep acceptors, while VAs-1, VAs-2, and VAs-3 defects would behave as donor defects. The antisites are amphoteric defects, whereas they will only behave as donor defects due to the Fermi-level should be below the conduction-band minimum of InGaAs side. For InAlAs/InGaAs devices, the impact of the cation vacancies (acceptors) and antisites (donors) is associated to the bias conditions, while it is bias-independent for As vacancies (donors).