A method for manufacturing an electrode, the method comprising: holding an electrode substrate having a rectangular plate-like shape, being formed with attachment portions (A1, A2) at two ends including opposing sides of the electrode substrate so that the electrode substrate is in a suspended state by a suspension jig and a lower jig at the attachment portions (A1, A2), comprising inserting one of the attachment portions (A1, A2) into the suspension jig; and inserting the other attachment portion (A2, A1) into the lower jig so as to perpendicularly suspend the electrode substrate with the suspension jig and the lower jig, and thereafter performing at least the heat treatment on the electrode formation surface while maintaining the electrode substrate in a suspended state so as to manufacture an electrode surface that is to be an electrode, characterized in that the attachment portions (A1, A2) are independently formed at the ends each including one side of the electrode substrate, and each of the attachment portions (A1, A2) is formed by bending two parts so that each part has an overall even side, and each of the attachment portions (A1, A2) includes a first planar portion that protrudes from the electrode formation surface as a first bent portion is formed by bending the electrode substrate in one surface of the electrode substrate; and a second planar portion that includes the one side as an edge and that is formed as a second bent portion is formed by bending an end of the first planar portion so as not to oppose the electrode formation surface and to face the same direction as the electrode formation surface, and wherein the suspension jig includes at least a placement portion (10, 12) having a planar shape, being configured to place the first planar portion; and a movement restriction portion having a contact surface (11, 13) with which the edge at a leading end of the second planar portion comes into contact, and wherein the lower jig includes at least a contact portion (10, 12) having a planar shape with which the first planar portion comes into contact; and a movement restriction portion having a contact surface (11, 13) with which the edge at the leading end of the second planar portion comes into contact. holding an electrode substrate having a rectangular plate-like shape, being formed with attachment portions (A1, A2) at two ends including opposing sides of the electrode substrate so that the electrode substrate is in a suspended state by a suspension jig and a lower jig at the attachment portions (A1, A2), comprising inserting one of the attachment portions (A1, A2) into the suspension jig; and inserting the other attachment portion (A2, A1) into the lower jig so as to perpendicularly suspend the electrode substrate with the suspension jig and the lower jig, and thereafter performing at least the heat treatment on the electrode formation surface while maintaining the electrode substrate in a suspended state so as to manufacture an electrode surface that is to be an electrode, characterized in that the attachment portions (A1, A2) are independently formed at the ends each including one side of the electrode substrate, and each of the attachment portions (A1, A2) is formed by bending two parts so that each part has an overall even side, and each of the attachment portions (A1, A2) includes a first planar portion that protrudes from the electrode formation surface as a first bent portion is formed by bending the electrode substrate in one surface of the electrode substrate; and a second planar portion that includes the one side as an edge and that is formed as a second bent portion is formed by bending an end of the first planar portion so as not to oppose the electrode formation surface and to face the same direction as the electrode formation surface, and wherein the suspension jig includes at least a placement portion (10, 12) having a planar shape, being configured to place the first planar portion; and a movement restriction portion having a contact surface (11, 13) with which the edge at a leading end of the second planar portion comes into contact, and wherein the lower jig includes at least a contact portion (10, 12) having a planar shape with which the first planar portion comes into contact; and a movement restriction portion having a contact surface (11, 13) with which the edge at the leading end of the second planar portion comes into contact.