In order to increase the bandwidth of the horizontal omnidirectional antenna, a new type of wide-band horizontal polarization omnidirectional antenna is designed. The antenna consists of an array of four arc-shaped dipole antennas forming a ring, and each dipole antenna is printed on the upper and lower surfaces of the Printed Circuit Board(PCB). The radiation fields of the four arc-shaped dipole antennas add together and compose a horizontal omnidirectional pattern in the far field. By slitting each dipole element and loading parasitic patches on the edge of the printed board, the bandwidth of the antenna is increased. An antenna sample is designed and manufactured. The measured results show that the antenna can achieve |S11|<10 dB in 2-3.71 GHz, the relative bandwidth is 60%, the mean gain of its horizontal omnidirectional is about 1.36 dBi, and the non-roundness of its horizontal omnidirectional pattern is less than ±1.5 dB. The test results are in good agreement with the simulation results.