1016001Wireless Power Transfer (WPT) and energy harvesting technologies are expected to provide revolutionary technological changes in important fields such as 5G communications and the Internet of Things. The short-range coupling WPT has gradually been commercialized, but there are still many technical bottlenecks in the practical process of microwave power transmission that can realize long-distance applications, such as the contradiction between the limited aperture of transceiver antennas and the WPT efficiency. The developments of electromagnetic metamaterials and metasurfaces have brought new breakthroughs for solving the above-mentioned problems. In this paper, we will focus on the combination of the two important technologies, and systematically review the applications of metamaterials in microwave wireless power transfer and wireless energy harvesting. The results show that the near-field focusing metasurface can significantly improve the transfer efficiency. We will also introduce the research progress of optically transparent metasurfaces and reconfigurable metasurfaces for improving WPT performance and practicability. Based on the periodically close arrangements of subwavelength metamaterial units, a wireless energy harvester with wide-angle incidence and polarization-insensitive characteristics is designed, which can replace conventional receiving antennas with higher harvesting efficiency. Furthermore, coplanar integration with the rectifying diodes makes a new concept of the rectifying metasurface, which can simplify the overall structure, reduce the size, and improve the efficiency. Finally, we will discuss the future progress of WPT, and point out the vital role that programmable and intelligent metamaterial technologies will play very important roles in future simultaneous wireless information and power transfer systems.