The device comprises a toilet bowl (12) for handicapped person, in a room (1) comprising an opening (10) to the side of which can be park a motor vehicle, a mobile folding seat (11), comprising a seat for the user, the guide means (9) of said foldaway said mobile folding seat (11) which can be moved on the said guide means (9) between an advanced position is located at the side and in the vicinity of the vehicles seat of the user, stopped in a determined position on the side of said opening of the room, and a transfer location, in which the folding seat (11) and the cup (12) are located beside one another and in the immediate proximity
