Abstract: According to at least one embodiment, the present disclosure provides an electronic braking system comprising: a main master cylinder including a main body, a main piston that is accommodated to be movable in the main body, a main chamber that is defined in the main body and connected with at least one wheel brake, a motor that generates a rotation force, and a power conversion unit that has one side connected with the motor and another side connected with the main piston, and converts a rotational motion of the motor into a straight motion, the main master cylinder being configured to generate hydraulic pressure by movement of the main piston; a motor position sensor disposed to sense a rotation distance of the motor; and a braking controller configured to perform control to move the main piston to a preset initial position by calculating displacement of the main piston based on the rotation distance of the motor and adjusting an amount of a current that is supplied to the motor.