Pentamode Metamaterials (PMs) with anisotropic elastic tensor have potential applications for acoustic cloaking, so it is attracted a lot of research interest. In the review, pentamode materials and their recent progress are introduced. It includes the concept of PMs, the acoustic and elastic properties of Bragg scattering PMs and Local resonant type of PMs. The fabrications and measurement methods are also introduced. PMs perturbed structures have advantages of anisotropic elastic tensor and 3D complete acoustic bandgap, therefore they pro-vide a way for low-frequency acoustic cloaking.