The invention discloses a half-blade-rotor-type axial flow blood pump which comprises an inner barrel, a front guide, a rotor and a rear guide. The front guide has three straight blades, the rotor has two rotating blades, the two rotating blades of half-blade structures are distributed on a front half of a hub of the rotor only, and blade tip clearance length of the rotor is reduced by a half; the rear guide has three big rotating blades and three small rotating blades, the big rotating blades and the small rotating blades are distributed at intervals, each big rotating blade is provided with a suspension arm with one-half length, each suspension arm extends into a rotor area to form a suspension arm blade structure, and a runner portion on the outer surface of the rotor is made by smooth date-pit-shaped cubic spline curves. The half-blade-rotor-type axial flow blood pump has the advantages that a whole runner formed by the front guide, the rotor and the rear guide is designed to be of a date-pit-shaped structure, and the smooth cubic spline curves are adopted, so that pressure rise of the blood pump is increased, flow field distribution in the pump is improved, area of a rotating-stilling interface is reduced, and risk of thrombosis at a bearing is lowered.