Metal additive manufacturing has broad application prospects in the civil aviation. By comparing three typical metal additive manufacturing technologies, this paper summarizes the research of metal additive manufacturing in the DFAM, materials and process. The progress of typical applications is introduced according to the technical classification. Based on the special requirements for airworthiness certification in civil aviation, this paper analyzes several challenges such as immature design methods, low processing efficiency, limited quality monitoring methods, and lack of uniform airworthiness certification requirements, and looks forward to the future development trend.