Tharsis province is a major center of Martian volcanic activity characterized by large gravity and topography anomalies. The origin of Tharsis is debated. One hypothesis is that the province was produced by melting associated with a mantle plume from the core-mantle boundary. An alternative hypothesis is that Tharsis formed by a plume associated with an impact. Recent studies have shown that this hypothesis is plausible from a geodynamical point of view and that long-lived impact plumes might play a role in areoid evolution. In this study, the magmatic evolution of impact-induced thermochemical mantle plumes is investigated with fully three-dimensional spherical shell simulations of mantle convection. Melt volumes and emplacement rates predicted by the model can satisfy observational constraints on Tharsis development.