An information acquisition device for acquiring digital Information includes: a first transmission unit (14) having directivity and transmitting by wireless an information request signal to be transmitted in a direction of the directivity; an information addition unit (13) adding at least one piece of address information to the information request signal to be transmitted; a reception unit (15) receiving a radio signal transmitted by wireless in response to the information request signal transmitted by the first transmission unit, and acquiring information contained in the signal; an information storage unit (16) which is built in the information acquisition device or attached to the device as removable from the device, and can store all or a part of information acquired by the reception unit; and an operation unit (11) issuing an instruction to start an information requesting operation. The reception unit (15) has no directivity or has broader directivity than the first transmission unit.