A multiple throttle device mounted on an engine having a plurality of cylinders arranged in line, comprising: a throttle body having intake passages arranged corresponding to intake ports of cylinders of the engine; throttle valves situated in the intake passages; a throttle shaft that is rotatably disposed in the throttle body along the throttle valves arranged in line and supports the throttle valves so as to allow the throttle valves to be opened and closed; a drive section that drives the throttle shaft, and a sensor section that detects the opening of the throttle valves, wherein: the sensor section includes: a shaft member formed to have a different axis from the throttle shaft, the shaft member is positioned within the width of the throttle body and displaced with the throttle shaft; and a throttle position sensor that is disposed in the shaft member and detects the opening of the throttle valves by the displacement of the shaft member, characterized in that: the shaft member and the throttle position sensor are disposed on one side in a radial direction of the intake passages across the throttle shaft; and the drive section is disposed on the other side in the radial direction of the intake passages across the throttle shaft. a throttle body having intake passages arranged corresponding to intake ports of cylinders of the engine; throttle valves situated in the intake passages; a throttle shaft that is rotatably disposed in the throttle body along the throttle valves arranged in line and supports the throttle valves so as to allow the throttle valves to be opened and closed; a drive section that drives the throttle shaft, and a sensor section that detects the opening of the throttle valves, wherein: the sensor section includes: a shaft member formed to have a different axis from the throttle shaft, the shaft member is positioned within the width of the throttle body and displaced with the throttle shaft; and a throttle position sensor that is disposed in the shaft member and detects the opening of the throttle valves by the displacement of the shaft member, characterized in that: the shaft member and the throttle position sensor are disposed on one side in a radial direction of the intake passages across the throttle shaft; and the drive section is disposed on the other side in the radial direction of the intake passages across the throttle shaft. the sensor section includes: a shaft member formed to have a different axis from the throttle shaft, the shaft member is positioned within the width of the throttle body and displaced with the throttle shaft; and a throttle position sensor that is disposed in the shaft member and detects the opening of the throttle valves by the displacement of the shaft member, characterized in that: the shaft member and the throttle position sensor are disposed on one side in a radial direction of the intake passages across the throttle shaft; and the drive section is disposed on the other side in the radial direction of the intake passages across the throttle shaft. a shaft member formed to have a different axis from the throttle shaft, the shaft member is positioned within the width of the throttle body and displaced with the throttle shaft; and a throttle position sensor that is disposed in the shaft member and detects the opening of the throttle valves by the displacement of the shaft member, characterized in that: the shaft member and the throttle position sensor are disposed on one side in a radial direction of the intake passages across the throttle shaft; and the drive section is disposed on the other side in the radial direction of the intake passages across the throttle shaft. the shaft member and the throttle position sensor are disposed on one side in a radial direction of the intake passages across the throttle shaft; and the drive section is disposed on the other side in the radial direction of the intake passages across the throttle shaft.