Abstract: With development of stealth technology and the emergence and use of stealth fighters in various countries, it will pose a severe challenge to the early warning and detection system. Metric-wave radar has a strong advantage in detecting stealth targets. Metric-wave 3D radar adopts 2D AESA, uses elevation digital multi beam and super-resolution height measurement algorithm, can locatestealth targets in three coordinates, which is an important means of detecting stealth targets. In this paper, a 2D phase-scanned metric-wave 3D radar antenna is designed. The antenna works in metric-wave VHF band with a relative bandwidth 20??, and has wide angle scanning function in azimuth/ elevation ±45°range. The sum difference beam and multi beam is formed in azimuth/ elevation direction by DBF technology, to meet the needs of radar detection and intersection. The structure size of radar antenna is large, and the high-mobility transportation of radar antenna is realized by using the technology of oscillator unit lodging and array folding.