The recent progress of HfO 2 and ZrO 2 doped LiNbO 3 crystals was reviewed. LN:Hf crystal has similar optical damage resistance as LN:Mg， but LN:Zr has much better property than LN:Mg. LN:Fe，Hf and LN:Fe，Hf crystals have both fast photorefractive response speed and high saturation diffraction efficiency. And the distribution coefficient of ZrO 2 in LiNbO 3 is close to one. These results indicate that the tetravalent ions doped LiNbO 3 will be the excellent nonlinear optical crystals.