The　multi-beam　reflectarray　and　transmitarray　(TA)　antennas　are　new　antennas　that　can　have　wide　angular　coverage.　However,　they　are　generally　of　large　profiles.　To　address　the　issue,　this　article　proposes　a　folded　TA　antenna　of　high　gain　and　low　profile　that　can　produce　circularly　polarized　(CP)　multi-beams.　It　consists　of　a　main-reflector,　a　TA,　and　a　linearly　polarized　(LP)　planar　feeding　array.　It　reflects　an　incident　electromagnetic　wave　twice　and　converts　polarization　three　times.　It　has　a　metasurface　that　carries　out　the　broadband　LP-to-CP　conversion.　A　prototype　is　developed　with　a　height　of　1.8λ　at　13　GHz.　The　experimental　results　show　that　the　antenna　can　achieve　a　scanning　range　of　±10°,　a　peak　gain　of　22　dBi,　and　an　aperture　efficiency　of　20.8%.　It　has　a　3-dB　axial　ratio　bandwidth　of　2.2 GHz　(or　16.6%),　covering　12.1–14.3 GHz.　It　features　a　low　profile,　high　gain,　low　cost,　and　easy　integration　with　communication　systems　(e.g.,　MIMO　transceiver　systems).　©　2022　Wiley　Periodicals　LLC.