A gate device disposed between a first space where a person waiting for passing through exists and a second space where a person already passed through exists, the device including: a gate main body disposed along a path through which the person existing in the first space passes when the person moves to the second space; a shutter for blocking or opening the path; and a structure disposed on an upper surface of the gate main body and having a first sensing device for sensing a person passing through the path, and a second sensing device for sensing a person passing through a side opposite to the path across the gate main body.