Currently, China's urban gas supervisory control and data acquisition (SCADA) system faces numerous problems, such as weak information system architecture, incomplete information (& communication) infrastructure design, and an uneven development level. A capable comprehensive evaluation method is urgently needed to achieve a hierarchical design of their infrastructure. This study introduces a multi-level fuzzy comprehensive evaluation (FCE) method using the analytic hierarchy process (AHP), coupled with particle swarm optimization (PSO). By combining qualitative and quantitative analysis, an evaluation index system for a multi-dimensional SCADA-controlled urban gas infrastructure hierarchical design is developed based on the scale of operations, regional safety risk, and management situation. The consistency test, correction, and evaluation index weight value of the judgement matrix in AHP are transformed into a nonlinear constrained optimization problem, which is then solved using PSO. Then, combined with the fuzzy mathematical theory, the membership function is used to compute the membership levels of the indicators at all levels. Finally, the multi-dimensional and multi-index fuzzy comprehensive evaluation of the hierarchical design of SCADA-controlled gas infrastructure is implemented. The proposed evaluation approach was used to evaluate 20 branches of the Sichuan Chuangang Gas Company. The results show that the method is applicable to the hierarchical design of SCADA-controlled gas infrastructure and can serve as reference for other gas companies in developing SCADA-controlled gas infrastructure.