A core body of a reactor include an outer peripheral iron core, at least three iron cores arranged in contact with or coupled to an inner surface of the outer peripheral iron core, and at least three coils wound onto the at least three iron cores. Gaps, which can be magnetically coupled, are formed between the at least three iron cores. The reactor further includes a protection part which at least partially protects projection portions of the at least three coils which project from at least one end surface of the core body.