Abstarct: Kermanshah With a population of about one million people, it is currently the ninth most populous city and one of the major metropolises in Iran. Due to population growth And the development of economic activities, Amount of water demand is rising,So that Annually the water shortage is more tangible every year. in this research Kermanshah city water system In the During the period 1395- 1375, investigate using the Combined method of dynamics of systems and econometrics And simulated by 1407 Also, the relationship between the components of the system has been analyzed. Among the factors that affect the urban water system of Kermanshah are: water resources (surface and underground); factors affecting demand (population growth, industry development, household consumption, etc...The assumptions that Proven in this research are: 1-With increasing water prices, Kermanshah water shortage will decrease over time. 2- With increasing population of Kermanshah city, urban water demand With exponential growth increases over time as it grows. 3- With increasing subsidies, , urban water demand With exponential growth increases over time as it grows. Furthermore, In the scenario related to the demand side, It became clear that investing in installing reducing equipment Consumption could reduce water scarcity. Supply-side scenario Expresses that Investment to repair the network to reduce leakage Will reduce the city's water scarcity. In general, the simulated model can be used as a tool for policymakers to implement economic and managerial measures.The mechanism used in this area is also applicable to other areas where there is a shortage of water.