<p>NdFeB permanent magnets have found extensive applications across multiple engineering fields due to their outstanding magnetic properties. However, their inherent brittleness and subsequent fracture failures significantly limit their application scope. As a fundamental challenge in engineering safety, the mechanistic understanding of fracture behavior remains a research priority. The phase-field fracture method, an advanced numerical simulation technique developed in recent years, provides a novel approach for investigating material fracture behavior. Nevertheless, most existing phase-field fracture models rely on isotropic assumptions, inadequately capturing the anisotropic fracture behavior prevalent in engineering materials. This work proposes a dynamic polycrystalline phase-field fracture model incorporating material anisotropy and constructs polycrystalline models with stochastic grain geometries via Voronoi tessellation, achieving precise characterization of fracture behavior in anisotropic materials. Using sintered NdFeB magnets as a case study, this work systematically investigates the influence mechanisms of microstructural characteristics and loading rates on fracture behavior and mechanical responses, providing a theoretical basis for improving material properties.</p>