Abstract: In this paper, a new global optimization method is proposed to solve the multi-target space exploration trajectory design problem. The variables of targets selection, visiting sequences and launch windows are synchronously optimized. In the context of two-body model in which the central gravity of the sun is only considered with the thrust as impulse, the patched-conic method accompanied with differential evolution (DE) algorithm are applied to solve the global optimization trajectory design problem. Then the method is utilized to solve the problem of the Third National Design Competition for Deep Space Exploration and the example missions of the ACT of ESA. It proves that the global trajectory optimization design method is feasible and valuable for the problem of multi-target and multi-mission space trajectory design.