<p>The impact of ferrofluid droplets on hydrophobic cylindrical surfaces under magnetic fields has attracted increasing attention due to its potential applications in water repellence, anti-icing, and drag reduction. In this work, the anisotropic spreading dynamics of a ferrofluid droplet impacting an asymmetric geometric structure are systematically investigated through combined experimental, numerical, and theoretical analyses. The results show that the spreading behaviour of the ferrofluid droplet is primarily governed by the magnetic field strength, impact Weber number, and surface curvature ratio. As magnetic flux density increases, the axial spreading diameter decreases, while the time required to reach the maximum spreading grows correspondingly. A theoretical model is further developed to predict the maximum spreading diameter of ferrofluid droplets under the influence of magnetic fields, showing good agreement with experimental results.</p>