Provided are a method for welding a battery module and a welded structure, and more particularly, a method for welding a battery module and a welded structure, in which a plurality of battery cells provided with electrode tabs are assembled to form a module and a voltage measurement portion of a voltage measurement means is welded to the electrode tabs so as to secure stability against vibrations and external shocks, thereby increasing reliability of voltage measurement and the voltage measurement portion is welded to the electrode tabs using the same kind of materials so as to facilitate an operation and improve productivity.