The phase separation in Ni75AlxV25-x alloys incorporated with the elastic stress was investigated using the microscopic phase-field model. The final morphology of γ′ and θ is similar in spatial alignment, but the volume fraction of γ′ phase increases and that of θ decreases as the Al concentration increases. For the small elastic interactions of early-stage phase separation, the coarsening of γ′ and θ can be approximated by a linear growth law as predicated by Lifshitz and Slyozov and Wangner (LSW) theory. As the elastic interactions increase at late-stage coarsening, the growth rate decreases, and the growth presents quick increase at early-stage and slows down at late-stage.