An ultra-wideband has an elongated grounding plate disposed horizontally with a long front edge defined thereon. A connecting portion extends upwards from an end of the front edge. A first antenna radiator includes a first radiating strip extended from a side of the connecting portion and a second radiating strip connecting with a free end of the first radiating strip. A third antenna radiator includes a third radiating strip suspended over the grounding plate, a fourth radiating strip connecting with an end of a long front edge of the third radiating strip and an upper side of the second radiating strip, a fifth radiating strip extended downwards from the long front edge of the third radiating strip connecting with the connecting portion. A third antenna radiator extends downwards from a middle of the long front edge of the third radiating strip. A feeding point disposes on the second radiating strip.