To provide a getting in and out assisting device for a vehicle, capable of reducing an occupant's physical load in his getting in and out the vehicle.

This getting in and out assisting device for a vehicle assists an occupant at the rear seat of the vehicle having seats disposed in the longitudinal direction to perform the getting in and out movement. The device includes a front seat whose seat back is divided into at least two upper and lower parts, so that the respective parts are independently and relatively connected to be rotatable, a getting in and out start detecting means for detecting the start of an occupant's getting in and out movement at the rear seat, a seat back upper part driving means for turning the upper part of the seat back of the front seat forward or backward in the vehicle, and a control means for laying down the upper part of the front seat back forward or backward in the vehicle by the seat back upper part driving means when the getting in and out start detecting means detects the start of the occupant's getting in and out at the rear seat.