A vehicle steering system having a structure of a steer-by-wire system that employs a laterally independent steering operation system, the vehicle steering system comprising: a steering operation mechanism configured to steer a steered wheel ; and an actuator as an electric motor configured to apply a drive force for steering the steered wheel to the steering operation mechanism , wherein the steering operation mechanism includes: an input shaft to which the drive force from the actuator is input; an output shaft configured to output the drive force from the input shaft to the steered wheel ; and a coupling mechanism configured to couple the input shaft and the output shaft to each other, and the output shaft constitutes a part of a suspension (S), is extensible and contractible in the axial direction (X2) of the output shaft , and is rotatable about a central axis (C2) of the output shaft , wherein the output shaft is used for a MacPherson-type suspension, one end of the output shaft is coupled to a knuckle configured to support the steered wheel , and the other end of the output shaft is coupled to the coupling mechanism , when the steered wheel is steered, which is by being turned about a kingpin axis (K), the output shaft pivots about a pivot center (C) defined at an intersection of the kingpin axis (K) and the central axis (C2), and the coupling mechanism includes a universal joint that transmits the drive force from the input shaft to the output shaft in a state in which the output shaft is angularly offset from the input shaft . a steering operation mechanism configured to steer a steered wheel ; and an actuator as an electric motor configured to apply a drive force for steering the steered wheel to the steering operation mechanism , wherein the steering operation mechanism includes: an input shaft to which the drive force from the actuator is input; an output shaft configured to output the drive force from the input shaft to the steered wheel ; and a coupling mechanism configured to couple the input shaft and the output shaft to each other, and an input shaft to which the drive force from the actuator is input; an output shaft configured to output the drive force from the input shaft to the steered wheel ; and a coupling mechanism configured to couple the input shaft and the output shaft to each other, and the output shaft constitutes a part of a suspension (S), is extensible and contractible in the axial direction (X2) of the output shaft , and is rotatable about a central axis (C2) of the output shaft , wherein the output shaft is used for a MacPherson-type suspension, one end of the output shaft is coupled to a knuckle configured to support the steered wheel , and the other end of the output shaft is coupled to the coupling mechanism , when the steered wheel is steered, which is by being turned about a kingpin axis (K), the output shaft pivots about a pivot center (C) defined at an intersection of the kingpin axis (K) and the central axis (C2), and the coupling mechanism includes a universal joint that transmits the drive force from the input shaft to the output shaft in a state in which the output shaft is angularly offset from the input shaft . <EOS>