A battery pack includes: a plurality of battery cells; busbars respectively connected to the plurality of battery cells; a holder accommodating the busbars; a sensing board seated on the holder, connected to the busbars, and extending in a wavy manner in a first direction; and sensing terminals connecting the busbars to the sensing board and being configured to detect state information about the plurality of battery cells. The sensing board has holes in both sides thereof, and the holder includes protrusions respectively inserted into the holes. In response to the sensing terminals moving, the holes in the sensing board move with respect to the protrusions to stretch the sensing board.