This experiment aimed to establish the calculation method of multi-component gas concentration field in rubber ring sealed packaging container with gas leakage and permeation. Based on the analysis of exchange modes of multi-component gas between outside and inside gasket seal structure and their computation methods, the arithmetical solution of differential equation and CFD method was created for simulation of multi-component gas in container, the change of the multi-component gas in container was simulated in long physical time. The results indicated that the two methods were effective for simulation of leaking and permeating of multi-component gas, the difference in two simulation results after 40-day storage was not higher than 3.2% . CFD method can simulate the concentration field of multi-component with instinctive superiority, and its simulation result was more reasonable. The computation simulation method for changing law of multi-component gas in sealed container considering leakage and permeation was established, as well as the numerical simulation method for changing law of multi-component gas field.