Travel Assistance Method and Travel Assistance Device

A travel assistance device includes a traveling boundary acquisition unit configured to acquire lane information around a subject vehicle, a surrounding object acquisition unit configured to acquire surrounding object information, an obstacle determination unit configured to determine whether an obstacle hindering travel of the subject vehicle is present, an avoidance determination unit configured to determine whether the subject vehicle is allowed to avoid the obstacle by a steering control, and a blind spot determination unit configured to determine whether a blind spot is present on an oncoming lane opposed to a travel direction. An avoidance section setting unit is configured to set an avoidance end position of an avoidance section to execute an avoidance control. A vehicle control unit is configured to generate a travel route for the subject vehicle to travel from an avoidance start position to the avoidance end position of the avoidance section.