The task assignment of the manned/unmanned aerial vehicle formation in ground Time Critical Target (TCT) attacking was studied.Based on the general framework of the manned/unmanned aerial vehicle formation system and the concept of time-sensitive characteristic function, the task assignment model of the manned/unmanned aerial vehicle formation for cooperative ground TCT attacking was built. By adopting the improved Genetic Algorithm (GA), the matrix coding was introduced to enhance the task assignment efficiency. The timing sequence problem of task assignment was solved by introducing the decoding method for the deadlock problem.A simulation of the proposed algorithm was carried outand the result proved that this algorithm has high task assignment efficiency.