To provide an automobile brake system in which improvement in working efficiency and reduction of costs can be accomplished by simplifying constitution.

An automobile brake system 30 is provided with a first brake pedal 31, a second brake pedal 32, and a negative pressure type booster 1. When the first brake pedal 31 is operated, braking force can be applied to wheels 37, 38 by means of the negative pressure type booster 1. When the second brake pedal 32 is operated, the negative pressure type booster 1 receives electric power supply so as to be operated, and as a result, braking force can be applied to the wheels 37, 38.