The　PDE-based　image　restoration　has　drawn　much　attention　in　the　recent　years.　In　this　paper,　we　first　propose　two　novel　improved　models　based　on　the　Perona-Malik　anisotropic　diffusion　model　and　the　fourth-order　PDE　model,　respectively.　Then,　we　use　multi-grid　numerical　solutions　to　solve　our　PDE　models.　Numerical　experiments　show　that　our　improved　algorithms　are　efficient　and　fast　convergent.