The motivation of our research is to pursue a possibility of utilizing electric vehicles for the future operation of power transmission and distribution grids. In this paper, we report a Power-Hardware-In-the-Loop (Power-HIL) testing on the provision of Ancillary Service (AS) by in-vehicle batteries. The AS of our interest is multi-objective in the sense that it simultaneously provides both primary frequency control reserve for a transmission grid and voltage support for a high-voltage distribution grid. The Power-HIL testing is crucial to validating the Multi-Objective AS because the dynamics of the grids and of power conditioning systems emerge in a common time scale, latter of which involves modeling difficulties and thus needs their inclusion as real physical devices, that is, Power-HIL. We show that the Multi-Objective AS is simulated consistently in a Power-HIL testbed and works effectively in a dynamic situation of transmission and distribution grids.