An SOS cardiopulmonary resuscitator comprises a human body fixing mechanism, a pressing mechanism, a power source and a control device. The human body fixing mechanism is a side U-shaped card board, and the lower wall end of the opening of the side U-shaped card board is provided with a fixing strap. The pressing mechanism consists of a motor I, a shaft plate, a connecting rod I and a pressing column. The upper part of the upper wall of the side U-shaped card board is provided with a casing, the motor I is installed in the casing, and a crank is fixed on the shaft of the motor. The upper wallof the side U-shaped card board is provided with a pressing column passing hole, and the pressing column extends out of the upper wall of the side U-shaped card board through the pressing column passing hole. The upper end of the pressing column is provided with an articulated shaft I, the shaft plate is provided with an articulated shaft II, the upper end of the connecting rod I is hinged with the shaft plate through the articulated shaft I, the lower end of the connecting rod is hinged with the pressing column through the articulated shaft II, the shaft plate, the connecting rod I and the pressing column constitute a crank slider structure, and the motor is electrically connected with the power source through the control device. According to the present invention, the pressing force of the SOS cardiopulmonary resuscitator is moderate, uniform, and effective, no harm is caused to patients, and the risk of rescuers being infected with infectious diseases is avoided at the same time.