Abstract: A focusing antenna includes a feed-in antenna unit, a supportive reflecting unit and a main reflecting unit. The feed-in antenna unit radiates polarization signals polarizing in a first direction. The supportive reflecting unit includes a plurality of reflecting elements reflecting the polarization signals to generate a plurality of first reflected signals. The main reflecting unit compensates phases of the first reflected signals and rotates a direction of the first reflected signals to generate a plurality of second reflected signals having an electric field with polarization in a second direction perpendicular to the first direction.