Since the modern computer architecture was suggested by Von Neumann in 1945, computer has become inevitable for our life. This brilliant growth of computer has been led by device miniaturization trend, so called Moore's law. Especially, the explosive growth of memory devices such as DRAM and Flash have played key role in huge enlarging utilization of computer. However, abrupt increase of data used for many applications in big data era provoke the excessive energy consumption of data center which results from the inefficiency of conventional memory-storage hierarchy. As a solution, the application of new memory devices has been brought up for innovative memory-storage hierarchy. In this paper, the current development status and prospect of new memory devices will be discussed.