The invention relates to a rotor for a compressible fluid pump, in particular a blood pump that can be introduced through a blood vessel into a patient's body, wherein said rotor comprises one or more conveying elements (15), is compressible and expandable between a first compressed state and a second radially expanded state, is made at least partially from a plastic reinforced with reinforcing elements, in particular fibers (10, 11, 13, 18, 19, 55, 56, 62, 63) and is provided for rotation about an axis of rotation (14). According to the invention, the rotor is tensioned in the first, compressed state and free from external stresses in the second, expanded state. A third state exists, which the rotor (42) occupies in the operating state under load. The reinforcing elements, in particular fibers, extend in the rotor in the third state at least in sections in a stretched manner.
