The present invention relates to a flight time assignment system and a corresponding method. The method comprises: S1. selecting a specified number of flights to enter a candidate waiting pool and serve as candidate flights; and S2. selecting, when the flight in a queue misses a given flight time, a candidate flight to use the given flight time of the flight that misses the given flight time. For the global assignment of flights, the flights in each queue and candidate flights have a coincident route part, and a candidate flight is selected to use the missed given flight time according to the moment when the flight arrives at a certain flight point on the coincident route part. The present invention can implement quick and efficient assignment of flight times within a global scope.