To increase convenience of an operation performed from a vehicle stop state until ACC is started or resumed, provided is a driving assistance device for a vehicle, including: a control unit (11) configured to execute travel control of at least one of constant-speed travel control or follow-up travel control, and to stop the travel control during stop of the own vehicle (100); a detection unit (43, 13) configured to detect release of a brake pedal by an occupant of the own vehicle (100); and a reception unit (60, 13) configured to receive an assistance request from the occupant. The control unit (11) is configured to execute one of start or resumption of the travel control when the detection unit (43, 13) detects the release of the brake pedal and the reception unit (60, 13) receives the assistance request during the stop of the own vehicle (100).