A driving support apparatus of a vehicle, the vehicle comprising: a steering torque assisting device capable of assisting a steering torque applied to a steering input shaft via a steering wheel; and a rudder angle varying device capable of varying a relation between a steering angle as a rotation angle of the steering input shaft and a rudder angle as a rotation angle of steered wheels by relatively rotating a steering output shaft coupled with the steered wheels with respect to the steering input shaft, said driving support apparatus comprising: a first setting device for setting a first control target value corresponding to one of the steering torque assisting device and the rudder angle varying device, to make the vehicle follow a target driving route; a first controlling device for controlling the one device on the basis of the set first control target value; a second setting device for setting a second control target value corresponding to the other device of the steering torque assisting device and the rudder angle varying device so as to suppress a change in behavior of the vehicle caused when the vehicle is made follow the target driving route due to the control on the basis of said set first control target of the one device; and a second controlling device for controlling the other device on the basis of the set second control target value, said first setting device sets a target assist torque as the first control target value, said first controlling device controls the steering torque assisting device on the basis of the set target assist torque, said second setting device sets a steering transmission ratio for defining a rotation angle of the steering output shaft with respect to the steering angle so as to reduce the steering transmission ratio in comparison with when following for the target driving route is not performed, as the second control target value, and said second controlling device controls the rudder angle varying device on the basis of the set steering transmission ratio. a steering torque assisting device capable of assisting a steering torque applied to a steering input shaft via a steering wheel; and a rudder angle varying device capable of varying a relation between a steering angle as a rotation angle of the steering input shaft and a rudder angle as a rotation angle of steered wheels by relatively rotating a steering output shaft coupled with the steered wheels with respect to the steering input shaft, said driving support apparatus comprising: a first setting device for setting a first control target value corresponding to one of the steering torque assisting device and the rudder angle varying device, to make the vehicle follow a target driving route; a first controlling device for controlling the one device on the basis of the set first control target value; a second setting device for setting a second control target value corresponding to the other device of the steering torque assisting device and the rudder angle varying device so as to suppress a change in behavior of the vehicle caused when the vehicle is made follow the target driving route due to the control on the basis of said set first control target of the one device; and a second controlling device for controlling the other device on the basis of the set second control target value, said first setting device sets a target assist torque as the first control target value, said first controlling device controls the steering torque assisting device on the basis of the set target assist torque, said second setting device sets a steering transmission ratio for defining a rotation angle of the steering output shaft with respect to the steering angle so as to reduce the steering transmission ratio in comparison with when following for the target driving route is not performed, as the second control target value, and said second controlling device controls the rudder angle varying device on the basis of the set steering transmission ratio. a first setting device for setting a first control target value corresponding to one of the steering torque assisting device and the rudder angle varying device, to make the vehicle follow a target driving route; a first controlling device for controlling the one device on the basis of the set first control target value; a second setting device for setting a second control target value corresponding to the other device of the steering torque assisting device and the rudder angle varying device so as to suppress a change in behavior of the vehicle caused when the vehicle is made follow the target driving route due to the control on the basis of said set first control target of the one device; and a second controlling device for controlling the other device on the basis of the set second control target value, said first setting device sets a target assist torque as the first control target value, said first controlling device controls the steering torque assisting device on the basis of the set target assist torque, said second setting device sets a steering transmission ratio for defining a rotation angle of the steering output shaft with respect to the steering angle so as to reduce the steering transmission ratio in comparison with when following for the target driving route is not performed, as the second control target value, and said second controlling device controls the rudder angle varying device on the basis of the set steering transmission ratio.