<p>Laser ultrafast heating technology is extensively applied to the micro-machining of metallic materials, of which the transient thermoelasto-diffusive responses analysis is crucial important for avoiding the unwanted vibrations and isolating the harmful stresses. Nevertheless, in such extreme non-isothermal environment, the inherent spatio-temporal nonlocal effects of the heat transport and electron–phonon coupling mechanism remain unconsidered on thermoelasto-diffusive constitutive models and heat-impact responses predictions. This work establishes nonlocal electron–phonon two-temperature thermoelastic diffusion theory with the aid of extended irreversible thermodynamics principles. By using Laplace transform method, the newly developed model is adopted to analyze the thermoelastic-diffusive responses of 1D metallic sandwich composites with perfect interfaces subjected to non-Gaussian laser irradiation. The dimensionless numerical results indicate that the increase of the spatio-temporal nonlocal parameters of electron temperature remarkably accelerate or decelerate propagation velocity of thermal wave. And the absolute peak values of stress and chemical potential are accordingly enlarged. The increasing laser energy density parameter lifts the maximum values of stress and chemical potential, which are lowered with the increase of pulse duration time parameter. Additionally, the different ratios of material physical parameters improve/reduce the impact responses of thermal, mechanical, or diffusive fields. This study is expected to extend the thermoelastic diffusion theory based on nonlocal electron–phonon two-temperature thermal transport mechanism in metallic materials, providing a theoretical basis for the optimized design of metal sandwich structures under laser heating condition.</p>