A battery module includes a battery cell stack constituted by a plurality of stacked pouch-shaped battery cells, a battery module housing configured to receive the battery cell stack, and a heat dissipation member coupled to a portion of the battery module housing, wherein the heat dissipation member has a through-hole formed in a heat dissipation plate disposed so as to face the battery cell stack and a sealing member is added to the through-hole, and a method of manufacturing the heat dissipation member. It is possible to effectively prevent thermal runaway of a battery cell that has caught fire while minimizing an increase in volume of the battery module.