Becaused of the real need of economic development subrogation betrays the “rule of warehousing” in its exercising effect. Its function has developed from “to assure the safety of creditor's rights” to “a way of exercising creditor's rights”. Thus the principle of equality of creditor's rights regulated by the tradition contract law has made a great change, which has been arousing questions in the civil law field. In terms of the laws in effect and the related theories in law philosophy, the article explores the real pursuit of equality of creditor's rights, which is a kind of opportunity equality, rather than an absolute result equality.