An antenna device includes: a first ground member; one or more first antennas which are connected to the first ground member and resonate in a first frequency band; a second ground member; one or more second antennas which are connected to the second ground member and resonate in a second frequency band; one or more first filters which connect the first and second ground members and attenuate a signal in the first frequency band; and one or more second filters which connect the first and second ground members at a position different from a position where the one or more first filters connect the first and second ground members and attenuate the signal in the first frequency band less than the one or more first filters.