A battery module including: a plurality of battery cells aligned in a direction, the battery cells each including a terminal portion on a surface thereof; and a bus bar configured to connect between the terminal portions of battery cells of the plurality of battery cells, the bus bar including through-regions through which the terminal portions of the battery cells respectively pass, and a connection region connecting the through-regions, and a through-region of the through-regions has two or more through-holes corresponding to each other and through which one of the terminal portions passes, and the terminal portions are forcibly inserted into the bus bar.