When a plurality of antenna elements tuned to respective different frequency bands are closely disposed, the performance (the band, the radiating pattern, and so on) of each antenna element may deteriorate. In order to solve the problem, a multiband antenna according to the present invention is provided with: a conductive reflection plate; a frequency selective surface that is disposed so as to at least partially face the conductive reflection plate, that transmits therethrough electromagnetic waves in a first frequency band, that reflects thereon electromagnetic waves in a second frequency band that is a higher frequency band than the first frequency band, and that has a plurality of openings; a plurality of first antenna elements that are disposed in a region sandwiched between the conductive reflection plate and the frequency selective surface and that are tuned to a first frequency included in the first frequency band; and a plurality of second antenna elements that are disposed on a surface opposite the surface of the frequency selective surface facing the first antenna elements, that are fed through feeders passing through the openings, and that are tuned to a second frequency included in the second frequency band.