Steering assistance device and steering assistance method

A steering assistance device comprising:

• a steering angle detection unit, which detects a steering angle of a vehicle;
• a first assistance unit, which performs steering assistance of the vehicle by using an oil pressure;
• a second assistance unit, which performs steering assistance of the vehicle by using an electrical power;
• a speed measurement unit, which measures a traveling speed of the vehicle;
• and
• a control unit, which causes the first assistance unit to perform steering assistance such that a steering assistance amount of the first assistance unit is reduced by a predetermined amount from the predetermined steering assistance amount and causes the second assistance unit to perform steering assistance, in a case where the first assistance unit can perform steering assistance at a steering assistance amount predetermined for the detected steering angle,
• wherein, in a case where the measured traveling speed is larger than the predetermined speed, the control unit increases the steering assistance amount of the first assistance unit in accordance with the steering angle as compared to the steering assistance amount of the second assistance unit.