A master cylinder including: a primary chamber; a first piston which is provided in the primary chamber, and has one portion that is moved to the outside of the primary chamber by pressing a pedal; a secondary chamber which is provided to be adjacent to the primary chamber; a second piston which is provided in the secondary chamber, and has one portion that protrudes to the outside of the secondary chamber and is provided to be spaced apart from the first piston at a predetermined interval; and a hydraulic line which connects the primary chamber and the secondary chamber, and is connected with a wheel cylinder, in which the first piston is moved by pressing the pedal, and after the first piston is moved at a predetermined interval, the first piston and the second piston come into contact with each other, and are moved together.