Disclosed is a battery module, which includes battery cells having electrode leads and a connection member for connecting the battery cells, wherein the battery cells are classified into a first battery group having battery cells disposed side by side in a first direction and a second battery group having battery cells disposed side by side in the first direction so that electrode leads of the battery cells thereof face electrode leads of the battery cells of the first battery group, wherein the connection member is located between the first and second battery groups, wherein the electrode leads of the battery cells are connected to the connection member, respectively, wherein an electrode lead of any one battery cell of the first battery group is in contact with any one of an upper surface and a lower surface of the connection member, and wherein an electrode lead of a facing battery cell of the second battery group, which is located to face the any one battery cell, is in contact with the other one of the upper surface and the lower surface of the connection member.