The invention discloses an ultra wide band horizontal polarized horizontal omnidirectional antenna, comprising at least three arms integrated antenna elements. The arms integrated antenna elements comprises a folded dipole element and a parallel feeder. The folded dipole element comprises two inverted U shaped conductor sheets that are mirror symmetric as the upper arm and the lower arm. The right ends of the two inverted U shaped conductor sheets are connected by bent portion. The left ends of the two inverted U shaped conductor sheets are disconnected and respectively connected with one of two parallel feeders. The at least three arms integrated antenna elements are rotationally distributed around a center point. The parallel feeder converges at the center point. The center point is a feed point. The ultra wide band horizontal polarized horizontal omnidirectional antenna utilizes a folded dipole as a radiation element, in order to obtain the high impedance and fed and broadband after arraying and parallel feed. The ultra wide band horizontal polarized horizontal omnidirectional antenna increases gains significantly, optimizes the maximum radiation direction, puts up and down into the ideal level, obtains better cross polarization ratio and improves efficiency significantly. The ultra wide bandwidth simplifies the design of feed network, and is more convenient to debug and optimize.