A rotary variable resistor includes an insulating substrate, a resistor pattern and a current collector pattern that are provided on the insulating substrate, a rotor that is mounted on the insulating substrate in a rotatable manner, and a slider that is mounted on the rotor and makes sliding contact with the resistor pattern and the current collector pattern to cause the resistor pattern and the current collector pattern to be conducted to each other. When a maximum dimension of the resistor pattern, which defines a variable resistor, is Z [mm] and electric linearity is L [%], Z≦4.0 and Z×L