Abstract: Taking 2004-2014 A-share non-financial industry listed company as a research sample, the paper systematically analyzes and verifies the mechanism of the influence of supply chain concentration on the cost of equity capital and the possible transmission path. The research results show that: the higher the concentration of supply chain, the higher the cost of corporate equity capital; the operational risk is an intermediary path in which supply chain concentration affects the cost of equity capital, that is, the higher concentration of supply chain in the enterprise will intensify its operational risks faced in turn lead to an increase in the cost of equity capital. The higher competitive position of enterprises can weaken the negative impact of supply chain concentration on the cost of equity capital, and the competitive position of enterprises affects the relationship between them by mitigating the business risk of the enterprise, that is, higher competitive position of enterprises has a strong ability to withstand risks, thus alleviating the operational risks caused by the concentration of supply chain, and then weakening the positive correlation between supply chain concentration and corporate equity capital costs.

Key words: competitive position of enterprise, supply chain concentration, operating risk, cost of equity capital