Abstract: In economics, credit and credit money are widely used concepts. However, the vagueness of concepts' definition directly leads to a superficial understanding of the nature of credit money, let alone the relationship between credit and money. This paper tries to redefine credit and credit money, ascertain the relationship between credit and credit money, disclose the nature of credit and credit money and put forward new opinions on interrelationship of credit and money, the origin and nature of money from the new perspective of contract.