A warning device for a vehicle comprising: an electric motor that applies steering assisting force to a steered mechanism of a vehicle; a torque detector that detects a steering torque (T); a phase compensator that executes phase compensation on the steering torque (T) detected by the torque detector ; a basic assist current value setting unit that sets a basic assist current value (Io*), based on a phase-compensated torque that is a steering torque the phase of which is compensated by the phase compensator ; a vibration wave generator that generates a warning vibration wave (le) having a prescribed frequency based on an operating state of the vehicle; a target current value computing unit that computes a target current value (I*) for the electric motor by adding the warning vibration wave (le) generated by the vibration wave generator to the basic assist current value (Io*) set by the basic assist current value setting unit ; and a motor controller that controls the electric motor based on the target current value (I*) computed by the target current value computing unit , wherein the phase compensator includes a characteristic switching unit that switches a frequency characteristic between a normal state where the warning vibration wave (le) is not generated by the vibration wave generator and a warning vibration wave (le) generated state where the warning vibration wave (le) is generated by the vibration wave generator , and the characteristic switching unit is configured to switch the frequency characteristic such that, in the warning vibration wave (le) generated state, a gain with respect to a prescribed frequency of the warning vibration (le) wave is smaller than a gain with respect to the prescribed frequency in the normal state, and a phase delay with respect to the prescribed frequency is smaller than a phase delay with respect to the prescribed frequency in the normal state. an electric motor that applies steering assisting force to a steered mechanism of a vehicle; a torque detector that detects a steering torque (T); a phase compensator that executes phase compensation on the steering torque (T) detected by the torque detector ; a basic assist current value setting unit that sets a basic assist current value (Io*), based on a phase-compensated torque that is a steering torque the phase of which is compensated by the phase compensator ; a vibration wave generator that generates a warning vibration wave (le) having a prescribed frequency based on an operating state of the vehicle; a target current value computing unit that computes a target current value (I*) for the electric motor by adding the warning vibration wave (le) generated by the vibration wave generator to the basic assist current value (Io*) set by the basic assist current value setting unit ; and a motor controller that controls the electric motor based on the target current value (I*) computed by the target current value computing unit , wherein the phase compensator includes a characteristic switching unit that switches a frequency characteristic between a normal state where the warning vibration wave (le) is not generated by the vibration wave generator and a warning vibration wave (le) generated state where the warning vibration wave (le) is generated by the vibration wave generator , and the characteristic switching unit is configured to switch the frequency characteristic such that, in the warning vibration wave (le) generated state, a gain with respect to a prescribed frequency of the warning vibration (le) wave is smaller than a gain with respect to the prescribed frequency in the normal state, and a phase delay with respect to the prescribed frequency is smaller than a phase delay with respect to the prescribed frequency in the normal state. <EOS>