To solve the number of coalition structure increase rapidly, algorithm SCS (search of coalition structure), fast dynamic formation of Agent coalition, is given. It can prune the graph of Agent coalition structure, decrease the searching space., and proved that after pruning, the number of coalition structure is n(k-1)^n-k of that before pruning. Finally, an experiment is given. This work can be seen as an improvement of Jennings and Sandholm’s related work.