Abstract: Fire risk Forcasting and early warning is important to the fire protection of city.Computational Fluid Dynamics technology has been used for outdoor fire risk evaluations of fire hazard and smoke spreads in city center.The relationship between wind effect and the fire spread among buildings was studied by 3 cases simulation: winter case,summer case and a fire case.Fire safety status and trend analysis map was drawn.5 grads alarm level was defined and recognized by colors and lines,which is useful for fire fighting,evacuation,and making of emergency advisory plan.Advises for emergency response management have been summarized based on study result.