Abstract: With the rapid development of economy and financial market, there are complex relationships between enterprises.Default of some enterprises may lead to other default or increase the possibility of default.This kind of risk is called associated credit risk. The influence of social relationships among entrepreneurs on the associated credit risk contagion among enterprises is studied. Firstly, a two-layer network is constructed, which is formed by entrepreneurs and enterprises. Secondly, the influence path of entrepreneur social relationship on the associated credit risk contagion is analyzed. Thirdly, an associated credit risk contagion model is proposed, and the influence of entrepreneur social network and two-layer network structure on the associated credit risk contagion is also discussed. The results show that:the contagion effect of associated credit riskis affected by the social relationships of entrepreneurs and the topological structure of two-layer network; the associated credit risk contagion in associated enterprise network may be inhibited by improving the similarity of entrepreneur social network and associated enterprise network. The research perspective of credit risk is expanded and decision-making basis to control risk are provided for banks and other financial institutions.

Key words: associated credit risk, social relationship, associated relationship, two-layer network, epidemic model