Water resources carrying capacity has a vital influence on the economic growth and social progress in a country or region，it’s a hotspot of research on water between science and system science. Taking Wuhan City for example，combine thewater resources subsystem，economic subsystem，social subsystem，the ecological environment subsystem and water pollution subsystem by using the system dynamic model，build the simulation model，then make comprehensive analysis of the obtained parameter values by osculation value method. In the end，received overall best solution in the process of implementation of“national economic and social development of wuhan city twelfth five-year program”.