A mounting device includes: a main plate (34) on which a wheelchair is to be mounted; a vehicle side plate (36) provided between one end of the main plate (34) and a vehicle body; a ground side plate (38) provided between another end of the main plate (34) and a ground surface (20) ; and first to third rotating shafts (40a to 40c) provided between the vehicle body and the vehicle side plate (36), and between each of the plates. A slope (22) is configured to include the main plate (34), the vehicle side plate (36), the ground side plate (38) and the first to third rotating shafts (40a to 40c). The slope (22) is provided so that the main plate (34) is displaced between a low position and a high position by rotating the first to third rotating shafts (40a to 40c) using a drive mechanism.