Virtual constellations provide an efficient solution for making full use of satellite resources. Firstly, it studies and designs a threetier coordinated operation mechanism of task and resource management, task and resource matching, task coordinating and planning. A threelayer dynamic interactive architecture model based on multi-agent is established. Then, this paper studies the screening target selection strategy of the virtual satellite cooperative task, the negotiated the contract bidding method and the negotiated the contract evaluation method based on the improved contract net protocol algorithm model. Finally, a simulation experiment case for the maritime target surveillance search scenario is established. The simulation results verify the rationality and feasibility of the operation mechanism and architecture of the virtual constellation. And the simulation results also verify the feasibility and validity of the virtual constellation mission planning algorithm based on the extended contract net protocol.