Abstract: This paper proposes a practical approach for real-time simulation of large deformation and ductile fracture. We adopt the oriented particles approach for robust and efficient simulation of large deformation and develop a practical model for plastic flow and fracture. The proposed method finds the optimal rotation and the optimal stretch in shape matching. The newly introduced optimal stretch leads to a material strain that can be employed in the plastic flow and fracture criteria. We also propose a graphics processing unit skinning method for real-time rendering of a deformed, fractured visual mesh. Experimental results show that the proposed method can robustly simulate large, elastoplastic deformation and ductile fracture of large visual meshes in real time.