A travel support device includes a planner adapted to plan vehicle travel modes to be respectively assigned to each of a plurality of sections into which a travel route from a current location to a destination is divided. To each of the sections, the planner is adapted to assign, based on a road load associated with each section, a travel mode among a first mode, in which the remaining energy charge of the battery of the vehicle is not maintained, and a second mode, in which the remaining energy charge of the battery is maintained. The planner is adapted to identify, from among the sections, an excessive altitude change section, in which a change of altitude is predicted to be greater than or equal to a predetermined value, and assign the second mode with priority to the excessive altitude change section.