Gyrocraft rotor hub body (1) in which each blade (2) is linked to the body (1) by articulations and linking members the body includes two strong elements (7, 8) whose planes are substantially parallel to each other and perpendicular to the axis of the mast (3) of the rotor. The two elements (7, 8) are separated from each other by a space which is of sufficient size to permit the housing of the articulations which are advantageously embodied in the form of laminated spherical stops (5), one of the armatures (16) of which moves integrally with the (17) is fixed with respect to the two elements of the hub body and is arranged in the vicinity of the periphery of these elements so as to constitute a rigid bracing. The two elements are rings, an external ring (7) and an internal ring (8) each forming a rigid rim and which are linked by a thin wall (9) of substantially cylindrical form, and which comprises at least as many openings (10) as there are blades (2) each opening (10) has dimensions sufficient for the passage of the linking and articulation members of the corresponding blade (2) with their angular flappings.