In a system for releasing a pedal of a motor vehicle in the event of a frontal impact, the pedal includes a first, inner element which is transversely pivoted on a support secured to a front portion of the body of the vehicle and is able to operate a control rod, and a second, outer element having a lower, lever portion, operable by the driver, and an upper portion transversely pivoted on the inner element. A pair of tongues are provided for securing the said first and second elements together, and a stop member is mounted on a portion of the passenger compartment behind the pedal. The system can assume a first, normal operating condition, in which the elements are secured to each other by the tongues, and in a second condition, in the event of a frontal impact, in which rearward movement of the pedal towards the stop member causes the tongues to yield, thus allowing the outer element of the pedal to rotate relative to the inner element.