The aim of this paper is to study the general rule and to analyze the system of the trust business supervision. This paper's basic perspective is "state adjustment" economic law theory. On this theory and some modern economics such as law philosophy, law economics, institutional economics and comparative institutional analysis, this thesis delves into the trust business supervision, which acts as one of the methods of state regulation on economy, and discusses its legal regulation, basic institutional system, its relation to other financial supervisions and its revolution on the background of social transition and law change. This paper explains the general law philosophy on modern economic law, and creates itself a basic logical framework; analyzes the internal mechanism of trust business supervisory law's emergence and evolution in light of the cost theory and institutional transition theory in institutional economics; discloses the characteristics and reasons between trust business supervisory systems of different countries in light of law economics and comparative institutional analysis; studies the rule and path of building supervisory system of trust business in china.The route of financial risk's transferring is from transaction cost to asymmetric information; then to negative externalities and from the unity