Terminal airspace (TMA)is the airspace centering several military and civil aviation airports with com-plex route structure,limited airspace resources,traffic flow,difficult management and considerable airspace com-plexity.A scientific and rational sectorization of TMA can optimize airspace resources,and sufficiently utilize the control of human resources to ensure the safety of TMA.The functional sectorization model was established based on the route structure of arriving and departing aircraft as well as controlling requirements.Based on principles of sectorization and topological relations within a network,the arrival and departure sectorization model was estab-lished,using tree based ant colony algorithm (ACO)searching.Shanghai TMA was taken as an example to be sectorizaed,and the result showed that this model was superior to traditional ones when arrival and departure routes were separated at dense airport terminal airspace.