A novel miniaturized high gain slot dipole array antenna for X-band radar application is proposed. This antenna has 2 emission elements to improve the antenna gain. A floating metal, which is not connected to antenna metal layer, is placed to the back of the antenna in order to achieve the one sided directional radiation. The RF signal is fed through the miniaturized coaxial connector to coplanar waveguide (CPW). The simulation and the measured results of the return losses, gains, and radiation patterns are shown in this paper. The maximum peak gain of this antenna has 7.09dBi at 10.8GHz and front to back ratio is about 15dB. The size of the antenna is 18mm × 6mm × 0.436mm. Proposed antenna realized a high gain and miniaturization.