The accuracy of a measurement value obtained by a tire pressure detection device is lowered by a centrifugal force and an inertial force during travel. A pressure sensor (30) displaces a diaphragm (20) in its vertical direction (32) according to the pressure. The pressure sensor (30) is arranged in a tire (2) with the vertical direction (32) directed to a direction parallel to a rotation axis (34) instead of the tire circumferential direction or radial direction. The pressure sensor (30) is mounted onto a substrate with the vertical direction (32) of its diaphragm (20) directed in parallel to the substrate surface and the substrate is bonded to a tread portion of the tire (2) and a wheel rim portion while adjusting the vertical direction (32) of the diaphragm (20) with the direction of the rotation axis (34).