This paper studied a design of the confined space to provide a safe and reliable operating platform for no-oxygen packing technology. The space sealed technology was investigated, the sealing materials were analyzed, and the sealing structure and the calculation method were designed. In combination with the related experiments and the actual demands of production process, a solution of confined space was proposed. The whole structure of confined space was designed, especially for the sealing structures of key parts, and the related strengths and the oxygen leakage rate were analyzed. The designed confined space could meet the demand of continuous production of no-oxygen packaging. Using the confined space system designed in this paper, the convenient and reliable operation of packing equipment was achieved, and the remaining oxygen was lower than 0.0001% for a long time, meeting the demands of no-oxygen packaging technology.