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A modified first-principles-based atomistic method incorporating the anisotropic shell model is developed for the simulation of the vortex type polarization in polycrystalline ferroelectric.Based on the modified model, a series of distinct vortex and anti-vortex polarization configurations are obtained at atomic scale simulation in which the anti-vortex polarization configuration in polycrystalline ferroelectric has never been reported in the open literature.In this study, a standard definition is given to the polarized anti-vortex in mathematics and polarization topology.The accurate distribution has been obtained from the simulation and validated by analogy of the vortex field using the Landau-Ginzburg-Devonshire theory.The properties of the anti-vortex are studied to establish the relationship among the polarization value of the vector, the radius and the streamlines curvature of the anti-vortex.Based on the polarization mechanism, a method is proposed for experimenters to observe clearly and position accurately the polarization anti-vortex and vortex, which could combine as novel domain structure.