PURPOSE: To provide a opening closing position detecting device for a car which is constituted to easily cope with a situation regardless of the width and a type of a car door.

CONSTITUTION: A proximity switch unit 3 is arranged at a door drive part attaching plate placed on the upper part of the upper beam of a car and a sprocket is inserted in the drive shaft 3c of the proximity switch unit 3. A chain is run around the sprocket and the sprocket of the reduction gear of a drive part for a car door. In the proximity switch unit 3, a box is formed by using a bottom plate 3a and a cover 3b and the drive shaft 3c is extended through the bottom plate 3a. In the drive shaft 3c, a plurality of detection sheets 9 are inserted in the box. The detecting sheet 9 laterally rotated togetherwith the reduction gear is detected by a proximity switch 10 fixed at a stay 10a erected on the bottom plate 3a and the opening closing position of the car door is detected.