The present invention relates to an apparatus and method for manufacturing an electrode assembly. The method for manufacturing the electrode assembly comprises a melting induction process of inducing melting on an outer surface of a separator by a melting induction solvent to increase an adhesion force of an interface between an electrode and the separator and a lamination process of alternately combining and laminating the electrode and the separator, wherein the melting induction process comprises a vaporization process of vaporizing the melting induction solvent to form a space that is humidified by vapor, and the electrode and the separator are disposed in the space that is humidified by the vapor to induce the uniform melting on the outer surface of the separator.