The invention provides an intraventricular pulsating blood pump fixedly disposed at the ventricularapex inside the ventricle to generate pulsation action. The pulsating blood pump is substantially jellyfish-shaped and includes a bell-shaped pump body and a driving source, an opening of the bell-shaped pump body faces to the outlet of the ventricle, the driving source drives the bell-shaped pump body to contract or relax, and the contraction or relaxation of the bell-shaped pump body drives the blood in the ventricle to eject directionally to the artery and form a convoluted blood flow field between the inner wall of the bell-shaped pump body and the inner wall of the ventricle. The invention not only provides assist to ventricular by pulsating blood flow, but also optimizes the flow field and pressure distribution in the ventricle, the blood pump of the invention is better in biocompatibility than the blood pumps in prior art.