To solve the manned-unmanned combat agents coalition formation problem in task enforcement, a method of the coalition formation strategy of task grouping first and the agents-group matching is adopted. The concept of task distance is introduced in order to make best use of the correlation transitivity between tasks. Then the tasks grouping strategy of coincident task requirement is designed and the grouping solution-finding method based on reachable matrix transform is presented. Considering the match degree priority and agent capability utilization efficiency in combat agents and task groups, the combat agent and task group match strategy based on auction mechanism is designed. A task coalition formation project under a given scenario is achieved by calculating, the resource redundancy of the formed task coalition is analyzed, which shows that the proposed coalition formation strategy and method are effective.