The simulation technical guide of the Civil Aviation Administration only provides the overall process, but does not provide specific methods and details. In order to achieve airspace capacity assessment based on computer simulation models, the AirTOP software was used to take Urumqi terminal area and Xinjiang region airspace as examples. The specific practical methods and technical details from the clear research objectives to the whole process of model output analysis were given. The elements and precautions that should be considered in other special scenarios such as common activities of other airspace users and future multi-runway operation were discussed. The research shows that the simulation model obtained by using the above methods is consistent with reality, and the output indicators have reference significance, in order to provide methodological reference for other projects.