In lane keep control apparatus and method for an automotive vehicle, a
deviation tendency detecting section detects whether the vehicle has a
tendency of a deviation from a traveling traffic lane and a deviation
avoidance controlling section performs a control for the vehicle to
travel on a road surface which is parallel to the traveling traffic lane
when the deviation tendency detecting section detects that the vehicle
has the tendency of the deviation from the traveling traffic lane and,
thereafter, performs a control to prevent a yaw angle of the vehicle with
respect to the traveling traffic lane from increasing in a direction in
which the tendency of the deviation becomes large.