Abstract: In ancient China, the "illegal profiteering" system reflected the institutional rationality of the self-discipline of feudal autocratic power. However, under the stimulation of huge interests of usury and the structure of state monopoly property rights, harsh laws throughout history have failed to eliminate usury. Through the analysis of the "illegal profiteering" system with the method of new institutional economics, we find out that the dissimilation of state control by bureaucrats and landowners' interest groups and their monopoly of private usury in history made it difficult to curb usury. The internal economic root that affects the implementation of the system is the fundamental driving force of the system change. Regulation of usury cannot rely on prohibitive legal norms, it is more important to promote incentive law system that contribute to the healthy development of the lending market by establishing ownership structure that competes with usury through market mechanism, to implement capital allocation of resources through interest rate liberalization, and to develop inclusive finance to meet the needs of society for lending relying on private economic organizations.

Key words: usury governance, illegal profiteering, system evolution, market mechanism