Abstract: In order to realize the vacuum sealing of the radial line between the input and the output section, optimize the topology of high-power array antenna, the paper presents a scheme of radial line ceramics sealing window. Based on the pattern matching method, the radial line ceramic sealing window of the transmission and reflection characteristics is analyzed. On this basis, simulation designed to improve the structure of the implementation, reducing the impact on the sealing window’s surface field of the triple point and mutation in the structure. The results show that: this radial line sealing window’s reflected coefficient is less than 0.1, and power capacity attain is about 150MW.