Abstract: In order to obtain an antenna with ideal characteristics that can be applied to engineering, a planar structured microstrip array antenna was designed in the Ku band. The radiation patch structure of the microstrip antenna is designed. On this basis, the design of the feed network and the 8-element array antenna is completed. The array antenna model is constructed by CST simulation software, and the size parameters of the antenna are optimized. Finally, the antenna S parameters, standing wave characteristics and gain pattern are obtained. Simulation results show that the microstrip array antenna has high gain and low side lobe characteristics, and has good directivity, and has high practical value, and can be used in antenna engineering.