A passenger protection system for a vehicle having a door opening to which a door is attached. The system has an airbag attached in a folded form along an upper edge of the door opening, wherein when being expanded, the airbag is deployed along an inner side surface of an interior of the vehicle in a drawn curtain form; a contact detecting device for detecting a contact action of a passenger in the vehicle with the contact detecting device; and a control device for determining whether a passenger is close to the inner side surface based on a result of detection of the contact detecting device, and prohibiting deployment of the airbag while determining that a passenger is close to the inner side surface. The contact detecting device may have an elongated form in a length direction of the vehicle and consist of divided portions separated in a vertical direction.