A three-phase AC reactor according to an embodiment of the present invention includes an input and output terminal block; a peripheral iron core disposed under the input and output terminal block; and at least three iron-core coils each constituted of an iron core and a coil wound around the iron core, so as to contact an inner surface of the peripheral iron core or so as to be coupled to the inner surface. The at least three iron-core coils form gaps that can be magnetically coupled between two of the iron-core coils adjoining each other. The three-phase AC reactor includes a phase-based coil extending member unit that extends from coil end portions of the coils as base points to connection points of the input and output terminal block.