In this paper, the influence mechanism of market access mechanism on sales volume of aerospace components was studied by multilevel structural equation model. The research shows that the market access mechanism has a significant positive effect on sales volume and its direct effect has an explanation rate of 43%. The market access mechanism has moderation effect in the relationship between the market demand and the sales volume. Market competition factor and enterprise operation factor both have mediation effects in the relationship between the market access mechanism and the sales volume, but their effects are opposite. Some phenomena found by the research, are enlightening for the enterprise strategy of aerospace components companies.