Efficacy is a key consideration in the construction of rule of law. By showing the effect of rule of law, and with public supervision, sector competition and mechanisms of leader promotion, efficacy is expected to effectively motivate the constructors of rule of law and assist them in setting the course of action and cracking the formalism in the construction of rule of law. If it is ignored, the construction of rule of law will be questioned in terms of its rationality and legality.There has been a long history of research on the efficacy of the rule of law in China. Literature review shows a clear picture of its development path and characteristics—from the efficacy of law to the efficacy of rule of law, and the emergence of typical research paradigms at different stages of development. At the earliest stage, only the qualitative method was applied to the research on efficacy of law. However, researchers turned to quantitative study due to the flaws of the qualitative method. In the switch from the research on the efficacy of law to the rule of law, especially to the quantitative research on the efficacy of rule of law, the China School of Rule of Law Practice(CSRLP)has played an indispensable role. The CSRLP demands of researchers to observe the efficacy of rule of law in practice by the quantitative method and to construct the effective approaches in action, which will provide a new perspective and a dynamic way of thinking in the research on the efficacy of rule of law.Among the efficacy theories abroad, Charles Sanders Peirce's Pragmaticism is representative and pertinent, and can serve as a frame of reference for our study on the efficacy of rule of law. Furthermore, Peirce's Pragmaticism has a number of fundamental principles in common with those of the CSRLP. For example, both of them focus on three aspects of ″practice,″ ″experiment″ and ″test,″ which justifies the paradigm shift in the research on the efficacy of China's rule of law, brings deeper insights for the CSRLP, and lays the foundation for expanding the application and ensuring the effect of evaluation of rule of law. The fundamental purpose of the research on the efficacy of rule of law is to crack the problem of poor efficacy of the rule of law in China. This efficacy is affected by various factors, such as politics, economy, culture, society and so on, but the main body is the primary and fundamental factor. When the representative bodies promoting the construction of rule of law, such as the government, the public, the legal persons, etc., have poor efficacy in practice, the urgency to realize the efficacy of rule of law becomes prominent. Various paths can be adopted to realize the efficacy of rule of law, and the evaluation of rule of law is an effective mechanism of reversal pressure. This evaluation should be present in the whole process of the construction of rule of law, and be an institutional guarantee in the realization of the efficacy of rule of law. As for the efficacy path with evaluation as its core, it is necessary to be practical in determining the target of the efficacy of rule of law, experimenting and evaluating the construction scheme of rule of law, and promoting the public participation in the evaluation of rule of law.