Disclosed are a stiffness gain mechanism (23) for a magnetic suspension bearing (20), a magnetic suspension bearing (20) comprising the stiffness gain mechanism (23), and a blood pump. The magnetic suspension bearing (20) comprises a stator (21) with stator teeth (211) and a rotor (22) arranged in the stator (21). The stiffness gain mechanism (23) comprises: a rotor permanent magnet (231), a stator permanent magnet (232), and an axial dynamic body (233). The rotor permanent magnet (231) and the rotor (22) of the magnetic suspension bearing (20) form a rotor assembly, and the rotor assembly has an asymmetric structure relative to a main plane (P) of the rotor (22)； and the stiffness gain mechanism (23) is configured such that the stator permanent magnet (232) produces a radial attraction on the rotor permanent magnet (231), the axial dynamic body (233) produces an axial repulsive force on the rotor permanent magnet (231), and the magnitude of the axial repulsive force is able to change with the change of the axial distance between the axial dynamic body (233) and the rotor permanent magnet (231). The stiffness gain mechanism (23) can increase the torsional stiffness of the rotor (22) of the magnetic suspension bearing (20) and contribute to the miniaturization of the magnetic suspension bearing (20).L'invention concerne un mécanisme de gain de rigidité (23) destiné à un palier de suspension magnétique (20), un palier de suspension magnétique (20) comprenant le mécanisme de gain de rigidité (23), et une pompe d'assistance circulatoire. Le palier de suspension magnétique (20) comprend un stator (21) comportant des dents de stator (211) et un rotor (22) disposé dans le stator (21). Le mécanisme de gain de rigidité (23) comprend : un aimant permanent de rotor (231), un aimant permanent de stator (232), et un corps dynamique axial (233). L'aimant permanent de rotor (231) et le rotor (22) du palier de suspension magnétique (20) forment un ensemble rotor, et l'ensemble roto
