China's economy and finance are constantly developing, and the demand for corporate debt financing is soaring. As of the end of August 2020, the stock of China's bond market has reached 112 trillion yuan. Corporate bonds can enable companies to reduce financing costs, diversify risks, and allocate resources rationally. However, there is also the possibility of loss in corporate bonds. In the first half of 2019, my country’s bond market added 25 defaulting issuers, involving a total of 59 maturing default bonds, with a total default amount of about 30.339 billion yuan. Among the risks faced by corporate bonds, the most important risk is credit risk. This paper conducts empirical research by collecting data on my country’s corporate bond market, constructs 12 indicator systems, uses principal component analysis to extract five principal component indicators, and finally draws corresponding conclusions: The profitability and solvency of an enterprise are the key to distinguishing the credit rating of an enterprise. It is the main factor distinguishing the two types of corporate bonds, and it is also the focus of attention when investors invest.