For meeting requirements of high performance metal material laser additive manufacturing for stable atmosphere requirements, design and research on large-scale atmosphere protection environment system in large-scale powder-feeding laser additive manufacturing equipment. Based on the characteristics of the traditional inert gas environment, design the metal material laser additive manufacturing atmosphere protection environment system, use ANSYS software to carry out table and reliable simulation calculation analysis on system core, and optimize the technique process of inert gas environment formation and verify it by test. The verification test results show that the system can greatly improve the formation efficiency, decrease the cost, and improve the large-scale atmosphere protection environment fast formation and protection technology, which provides a fast and stable inert gas environment for the research of the forming process of high-performance metal material laser additive manufacturing.