The utility model belongs to the technical field of automobile parts, and particularly discloses a cycloidal fuel delivery pump of a high-pressure common rail fuel injection system, which consists of a fuel delivery pump body, an outer rotor, an inner rotor and a cross joint, wherein the fuel delivery pump is an integral structure; an inner rotor shaft and a pump body inner cavity are eccentrically and vertically arranged on the bottom surface of the inner cavity of the pump body by taking the radius of the central circle of the inner rotor shaft on the bottom surface of the inner cavity of the pump body as the symmetric axis; the low-pressure fuel cavity and the high-pressure fuel cavity of a half-moon shaped groove are symmetrically arranged on the bottom surface of the inner cavity of the pump body, the low-pressure fuel cavity is on the right side, and the fuel inlet at the lower end of the bottom surface of the low-pressure fuel cavity is communicated with the fuel intake joint on the back of the fuel delivery pump; and the inner rotors and the outer rotors with the gear petal structures are formed into a pair of eccentric internal engaged rotors. By adopting the integrally-structured pump body and axial fuel intake, the structure is compact, the size is small, and possibility of forming cavitation is low; as the gears are engaged during the working and circulating processes of the inner and outer rotors, the operation is stable, the pulsation is small, the noise is low, and the volumetric efficiency is high; therefore, the cycloidal fuel delivery pump of the high-pressure common rail fuel injection system is applicable to the diesel engine fuel injection system of the automobile.