A battery pack increases coupled strength of a protection circuit module and an outer case, and realize a compact battery pack by physically coupling the protection circuit module coupled to a bare cell and the integral outer case by an adherent member. The battery pack includes a bare cell; a circuit module arranged on an upper surface of the bare cell and electrically coupled to the bare cell; an outer case integrally formed so as to cover a pair of short side surfaces and the upper surface of the bare cell including the circuit module, and coupled to the circuit module; and a label attached to the pair of the short side surfaces, a pair of long side surfaces and a lower surface of the bare cell. At least one protrusion part may be integrally formed an outer side surface of said circuitmodule. At least one tapered part may be integrally formed with said outer case.