The invention relates to a functional artificial system for a left ventricle and belongs to the field of biomedical engineering. The system is composed of a drive and control system, a sensor connecting line, a sensor, a driving shaft, a blood storage chamber, a hemispherical piston and an elastic seal film. The system is applied to treatment and assistance of a diastolic heart failure sufferer; and a system main body is fixed to a cardiac apex position, penetrates through cardiac muscles and extends into the left ventricle, the elastic seal film is used for blocking off blood, the sensor is used for acquiring electrocardiosignals of the sufferer, the signals are transmitted to the drive and control system through the sensor connecting line, and the drive and control system is used for carrying out analysis processing on the electrocardiosignals, then, controlling the driving shaft to rotate, then driving the hemispherical piston to rotate, and thus, controlling the internal volume ofthe blood storage chamber and the contraction and dilatation of a heart of the sufferer to synchronously change. The blood storage of the left ventricle can be increased at diastole, and the volume ejection of the ventricle can be increased at systole.