DRIVING ASSISTANCE METHOD AND DRIVING ASSISTANCE DEVICE

The purpose of the present invention is to perform transfer from the system to the driver more reliably by lowering a level of driving assistance in a stepwise manner when it is ascertained in advance that steering wheel assist will be deactivated in a travel scenario involving a mode with a raised level of driving assistance.A vehicle speed/headway control function and a lane-keeping function are provided as driving assist functions to assist driving operations by a driver, and a mode transition controller (47) for transitioning between driving assist modes is provided. A lane disappearance region (S), in which no lane that continues from a current lane can be recognized, is detected along an extension of a travel route of a host vehicle during lane-keeping travel in which a "hands-off mode M1" has been selected. When the lane disappearance region (S) is detected, information on a lane disappearance start point (Ps1) is acquired, and a first position (P1) and a second position (P2) are set between a host vehicle position and the lane disappearance start point (Ps1). The first position (P1), the second position (P2), and the lane disappearance start point (Ps1) are used as mode transition positions, and the transitions "hands-off mode M1" → "hands-on mode M2" → "steering wheel operation mode M3" → "steering wheel assist deactivation mode M4" are performed.