During execution of lane keeping control, a vehicle driving support device sets a center line passing through a center of a travelable width of an own vehicle within a current lane as a target traveling line, and autonomously steers the own vehicle such that a reference point of the own vehicle moves along the target traveling line. The vehicle driving support device changes a position of the target traveling line such that the target traveling line is a line located between the center line and the reference point of the own vehicle, when a driver performs a steering operation for steering the own vehicle during the execution of the lane keeping control and a steering operation force of the driver becomes equal to or larger than a target change start threshold value.