In this study, a new design of dual-polarized ultra-wideband (UWB) antenna is proposed. The antenna design contains a circular ring slot radiator fed by two independently semi-arc-shaped microstrip feeding lines which can exhibit polarization diversity characteristic. A low-cost FR-4 dielectric (ɛ = 4.4, δ = 0.02) is used as the substrate. The characteristics of the dual-polarized UWB antenna are examined using both simulations and measurements and good results are achieved. An impedance bandwidth (S11  -10 dB) of 2.5-10.2 GHz with 121% fractional bandwidth (FBW) is achieved for the design. However, for S11  -6 dB, this value is more than 130% (2.2-11 GHz). The proposed UWB antenna offers good isolation, dual-polarized function, and sufficient efficiency which make it suitable for different applications such as radar and microwave imaging.