The present disclosure discloses a battery module having high safety and energy density while having stably cooling efficiency. The battery module of the present disclosure includes: a plurality of pouch-type secondary batteries standing in a vertical direction and stacked in a horizontal direction; a module case configured to accommodate the plurality of secondary batteries in an inner space thereof; a lower filling liquid filled in a lower region of the inner space of the module case and making contact with at least lower portions of the plurality of secondary batteries; and an upper filling liquid having a specific gravity less than a specific gravity of the lower filling liquid and filled in the inner space of the module case above the lower filling liquid.