The present invention relates to a battery pack. The present invention includes: a plurality of battery cells disposed in one direction; a heat transfer oil configured to contact surfaces of the battery cells; a frame configured to accommodate the battery cells and the heat transfer oil; a cooling plate configured to contact bottom surfaces of the battery cells through the frame and having cooling water flowing therein; and a battery management unit configured to manage heat generated from the battery cells by using at least one of a cell temperature of the battery cells, a temperature of the heat transfer oil, and a temperature of the cooling water.