Supply chain finance is now an effective way to solve the financing difficulties of SMEs ,Major banks have also set up special supply chain finance management, supply chain finance now is in a fierce rivalry. Banks vigorously carry out supply chain finance business, also bear some risks at the same time. Only properly handle the relationship between risk and return can obtain a favorable position in the supply chain finance market,this article learn from credit risk which is the major risk of supply chain finance adopt logistic model based on principal component and sample of steel industry supply chain financing to perform evaluation and analysis of the credit risk faced by banks