The invention relates to a heart massaging device. The heart massaging device comprises two clamping structures, a positioning device and a massaging device, wherein the two clamping structures are used for clamping the body of a patient; the positioning device is positioned between the clamping structures; the massaging device is arranged on the positioning device; the clamping structures clamp the body of the patient; and the massaging device is positioned at the heart of the patient. The clamping structures automatically clamp the body of the patient through the cooperation of the positioning device and the clamping structures, so the heart of the patient can be massaged without moving or turning the patient over. The heart massaging device can be applied in different places and can be automatically positioned at a proper part for heart massaging. The deviation of a massaged position can be avoided when the heart of the patient needing long-time emergency treatment is massaged, so that secondary hurt to the patient when the heart is massaged is reduced.