Abstract: As a key forming process that rapid,precise,and free manufacturing,3D printing plays an important role in promoting industrialization and industrial development.This article aims to introduce metal 3D printing technology,mainly focusing on selective laser metal additive forming,electrochemical metal additive manufacturing,electron beam metal additive manufacturing technology,and other aspects.It focuses on introducing and explaining their process principles and key technologies,and deeply explores the characteristics of additive manufacturing technology for preparing metal material components and its applications in daily life.At the same time,their forming mechanism was elaborated in detail and the main problems and challenges faced by metal 3D printing technology were discussed.Finally,the future development trends and research priorities in the field of metal additive manufacturing technology were prospected.