Wire arc additive manufacturing (WAAM) is one of the most rapidly developed additive-manufacturing technologies in recent years, which utilizes the arc as heat source to melt the metal wire, and realizes the forming of 3D solid metal components by depositing on the planned path. WAAM possesses the advantages of low manufacturing cost, high manufacturing freedom and high forming efficiency, especially suitable for the shape and properties integration forming of large size and low complexity components. In recent years, WAAM technology has received extensive research and development, and valuable researches have been achieved in the aspects of WAAM equipment, process control, metallurgical behavior of high-performance metal during WAAM process, etc. And there are mature application cases of WAAM for key metal components in aviation, aerospace, ship and other high-end manufacturing fields. This article presents a comprehensive overview of development of WAAM, including: WAAM equipment system, process control strategy, and metallurgical behavior of high-performance metal materials during WAAM process. The shortcomings of current researches are pointed out, and typical application cases of WAAM are listed. Finally, the future development direction of WAAM technology is prospected.