The quality and speed of development in natural gas science and technology is the core of promoting the natural gas industrial development. The construction of a natural gas scientific system through green development has both theoretical and practical significances for the sustainable development of natural gas industry. Therefore, a basic frame of Chinese natural gas industry in a scientific system with fundamental and composite structures is refined and purified by use of the system theory and the combination principle and according to the basic framework of the energy science system and the features of technical demand of natural gas industry chain. The fundamental structure is divided into three categories: (1)Basis (Type B): an energy & science-based fundamental structure of the natural gas scientific system, which includes basic theory, engineering, economic science, management science, etc. (2)Industry Chain (Type C): an industry chain based fundamental structure of science and technology, which is embodied in five fields of natural gas industry: exploration, exploitation, storage and transportation, marketing, and utilization. (3)Elements (Type E): an innovation-based fundamental structure of science and technology, which includes environmental sciences, politics, policy sciences, etc. related to the natural gas industry. Then, three composite structures are summarized: Type BC, BE, CE. Finally, this paper proposes strategies for the advancement of natural gas science and technology.