A battery pack including: a bare cell including an electrode assembly, and a can to house the electrode assembly; and a protective circuit board including a base plate, disposed on the can. The can includes a cap plate disposed in an opening thereof, including a first terminal that extends toward the protective circuit board. The protective circuit board includes a base plate, a first connection terminal connected to the first terminal, a second connection terminal connected to the cap plate, and a first opening corresponding to the first and second connection terminals.