Abstract: At first, this paper briefly sets forth the structural characteristics of the antenna of a large caliber, high precision, long range, air traffic control primary radar, and then describes the manufacturing technology used on double curvature reflector antenna and the measures adopted for guaranteeing its precision. With focus on the frame of antenna, which has a structure of plate butt welded box longeron, this paper expounds the riveting technological process for frames of monocoque reflector and the welding method employed on the framework of the antenna. This paper also introduces the antenna final assembly technological process. By establishing an appropriate system to allocate all components of antenna at correct position precisely, and with the help of technical equipment, dual electronic theodolite and digital photographic surveying technics, the root-mean-square error of the antenna array (15 m×7 m) is ≤1.5 mm.