By using a crab-like hydrazone ligand, dinuclear and tetranuclear dysprosium-based complexes Dy₂ and Dy₄ have been isolated. Magnetic investigation reveals that complex Dy₂ shows typical single-molecule magnet behavior under a zero field, benefiting from the ferromagnetic coupling between the Dy^III ions, while Dy₄ possesses a diamagnetic ground state with the anisotropy axes of Dy^III ions in centripetal arrangement. The magnetic anisotropies and couplings were confirmed by ab initio calculations.