Abstract: In order to meet the requirements of wide-angle beam coverage in wireless communication applications, an all-metal cavity-backed decoupling wide-angle scanning phased array is designed. The antenna works in the X-band and consists of a dipole with a slot balun, a standard subminiature push-on (SMP) connectors and a back cavity. The balun and the SMP are integrated in the design, and the back cavity is loaded at the section between the balun and the SMP. On the one hand, the back cavity can provide the vertical current for the antenna, thereby broadening the beam width of the active element pattern; on the other hand, an opposite phase couple currents is excited on the adjacent element, thereby reducing mutual coupling. The antenna has an impedance bandwidth from 8.6 GHz to 11.2 GHz (26.3%), and the mutual coupling between adjacent elements is less than −25 dB in the full operation band. The antenna can achieve beam scanning in the range of ±70° at 8.6 GHz to 9.3 GHz. The gain of the main beam reduces less than 2.4 dB and the sidelobe is less than −9.4 dB within the scanning range. At 9.3 GHz to 11.2 GHz, the antenna steers the main beam in the range of greater than ±45° with the gain fluctuation less than 2.5 dB and the sidelobe less than −10 dB. Antennas have the characteristics of wide-angle scanning, stable structure, and good robustness, making it valuable for applications in wireless communication systems.