The purpose of this study was to design a risk breakdown structure and prioritize its levels in Isfahan municipality. In this regard, the presentation of the objectives of the construction projects in project risk management has been considered. This research was conducted to determine the risk breakdown structure through comparative studies, semi-structured interviews, and a questionnaire. Finally, prioritizing the levels of risk breakdown structure, the objectives of the projects were accomplished through improved hierarchical fuzzy topology technique. Due to the fact that in classical Tapis, the mean value and standard deviation are not a complete measure for comparison of two fuzzy numbers, in order to eliminate this defect, the coefficient of variation has been used. This descriptive survey is of a survey type of a practical nature and periodic time. The data gathering tool included review of documentation, Delphi technique and researcher-made questionnaires by drawing an abstract ladder, its content and content validity was evaluated by Lavasheh method and its reliability was confirmed by the internal consistency determination method and in general 29 risk categories in The third level was identified and ranked in three levels and ranked in the second and third levels.