Provided is a composite (A) including a metal plate (B) and a reinforcing member (C) that is made of a resin. The metal plate (B) includes a joint portion (2) that is continuous with one end of a body portion (1), a hole that is formed through the body portion (1) in a thickness direction of the body portion (1) in the proximity of the joint portion (2), and a guide portion provided around the hole. The reinforcing member (C) continuously includes a main portion (5), a coupling portion (6) formed in the hole (3), and a locking portion (7) that is held in close contact with a surface on another side of the body portion (1). The guide portion (4) is at least one of a protruding portion provided on at least one of a rear side and a lateral side relative to the hole (3) in a direction from the body portion (1) to the joint portion (2), and a recessed portion extended from a front side relative to the hole (3) to the hole (3) in the direction from the body portion to the joint portion. In insert molding of the composite (A), a molten resin is introduced preferentially into the hole (3). With this, the joint portion (2) is formed reliably in good condition free from adhesion of the resin.