The metal additive manufacturing technique， as an importan t branch of 3D printing technique， has made remarkable progress based on the rapid development of materials technique， equipment technique， computer techniq ue， and so on. The evolution history of metal additive manufacturing technique i s reviewed briefly. The microstructure， the me chanical performance， the micro defect， and the technological process of product are introduced to discuss the studies on additive manufacturing technique of titanium allo y， nickel base superalloy， and so on. Some suggestions of technical problems in the development of additive manufacturing technique are put forward. Finally， the main development direction is pointed out.