A micro-miniature, light weighted and low cost trapezoid ultra wide antenna having an ultra wide band characteristics and a notch characteristic in 5 GHz WLAN band (5.15-5.35 GHz) is disclosed. The trapezoid ultra wide antenna includes: a dielectric substrate; a trapezoid shaped patch formed at an upper end of a middle line on an upper side of the dielectric substrate; a feeding line formed at a bottom end of the middle line on the upper side of the dielectric substrate for feeding electric power to the trapezoid shaped patch; a matching stub formed between the trapezoid shaped patch and the feeding line for impedance matching between the trapezoid shaped patch and the feeding line; and a ground formed at a side of the feeding line on the upper side of the dielectric substrate.