The invention relates to an aircraft track predication method of an air traffic control system. The air traffic control system comprises a data communication module, a monitoring data fusion module, an airborne terminal module and a control terminal module; the monitoring data fusion module is used for fusing air control radar monitoring data and automatic related monitoring data so as to provide real-time track information to the control terminal module; the control terminal module comprises a preflight conflict-free 4D track generation sub-module and an in-flight short-period 4D track generation sub-module. The aircraft track predication method of the system has the advantages that the flight plan data are processed through the control terminal module, and a 4D track is generated through a hidden markov model, so as to analyze the potential traffic conflict of the air traffic condition, and as a result, the safety of air traffic can be improved.