Research into sustainable development of urban gas is relatively sparse, and the evaluation of sustainable development based on the overall research into urban gas in China is still blank. Guided by system theory and analytic hierarchy processes (AHP), this paper took the sustainable development system of China's urban gas as a whole research object, and constructed the city gas sustainable development evaluation index system which consists of 5 subsystems and 47 specific indicators through primaries and screening indexes. On the basis of collecting and arranging a large amount of original index data, the authors analyzed and evaluated the sustainable development system of urban gas by using the factor analysis method. During 2002-2014, the development of each subsystem has shown an upward tendency, but with different performance. The economic subsystem fluctuates more widely, while the social subsystem continues to grow steadily. The resource subsystem developed fast early on and slowly in the latter stage. The development of the environment subsystem is best described as stable and slow, and the growth of the technology subsystem is most remarkable. Based on the multidimensional spatial structure model of urban gas subsystem movement, and combining the factor analysis evaluation results, this work calculates the development capacity, coordination ability, sustainable ability and sustainable development level of the urban gas system, and then evaluates its sustainable development. Overall, the development capacity of urban gas systems is increasing, the whole system reflects a high degree of coordination, and the sustainable ability has been improved steadily. Under this joint action, the sustainable development level of city gas industry has been increasing continuously.