This paper updates the progress in the applications of metamaterials-based antenna engineering at microwave bands. Based on the scientific concepts of metamaterials, the new technologies have been developed to greatly enhance the performance and reduce the volume of antennas. First, the strategy of research and development of metamaterials-based antenna technologies is introduced. Then, the metamaterials-based antennas are shown, including the composite left/right-handed leaky wave antennas, zero-indexed superstrate high-gain microstrip patch antennas, zero-phase-shift large coverage
near-field ultra-high frequency radio-frequency identification antennas and horizontally polarized omni-directional wireless-local-area-network antenna arrays, artificial magnetic conductor-loaded ultra-thin substrate-integrated Fabry-Perot cavity antennas, zero-index structure loaded high-gain tapered slot antenna, and broadband low-profile planar antennas. Some comments on the research and development of metamaterials in antenna engineering are also made.