The new discipline of development law, which aims to solve the development problem and promote the overall development, is highly coupled with the development strategies of Chinese-style modernization, and then provide a new perspective for the study of Chinese-style modernization. A two-way interaction exists between the new development strategy of Chinese-style modernization and the theoretical innovation of development law. On the one hand, the new development strategies of Chinese-style modernization construct the new background of development law, and require further innovation of the theory of systematism-based development law; on the other hand, the progressive innovations of the theory of systematism-based development law in the three dimensions of methodology, institutional system and theoretical system are conducive to promoting and guaranteeing the realization of Chinese-style modernization. Specifically, in terms of methodological innovation, development law, as a system science, should integrate system theory method and structure-function analysis method to conduct new comprehensive research centered on China’s development problem. This will guide the innovation of institutional system and theoretical system. In terms of institutional system innovation, the theory of systematism-based development law should start from promoting all-round development, innovate an inclusive institutional system that promotes Chinese-style modernization through reasonable allocation of the development rights, obligations and responsibilities. In terms of theoretical system innovation, the theory of systematism-based development law should further innovate in the aspects of genesis theory, ontology, axiology, normative theory, operation theory and category theory, and then construct China’s self-independent knowledge system of legal science in the field of development research, which is conducive to contributing a Chinese approach to the progress of international legal theory and the practice of international mutual development.