The present invention relates to a device for delaying a passenger air bag expansion, including a winding, shaft which is partially wound by a rear end of a tether. A support bracket rotatably supports both ends of winding shaft and is fixed to a bottom of an air bag housing. Winding shaft and support bracket are connected to each other through at least a pin to fix the winding shaft. Pin is broken by expansion force of the tether after a predetermined time period at an early stage of expansion of an air bag. Therefore, the expansion of the airbag cushion is delayed for a predetermined time. Since initial expansion force of airbag cushion is not strong, it prevents a child on a passenger seat from being struck by the airbag cushion.