The present invention discloses a battery pack which can prevent deformation and electrolyte leakage caused by external strike, wherein the battery pack includes a bare cell including a pouch type casing, an electrode assembly accommodated in the pouch type casing, and positive and negative electrode tabs extending out from one side of the pouch type casing; a protection circuit board electrically connected to the bare cell; and a main body accommodating the bare cell and the protection circuit board. The battery pack also includes at least one reinforcing plate, wherein an end of the at least one reinforcing plate is in contact with a surface of a front end portion of the bare cell. The reinforcing plate can be a whole with the upper or lower housing of the main body, or separate formed or set in upper or lower housing.