Based on the composition and operation characteristics of the joint test system in maritime range, it is the foundation of constructing the joint test environment of internal and external field to establish the simulation mission space which is consistent with the description of time and space. The influence of space-time inconsistency on the test results is analyzed, and the index of space-time consistency of the system is designed. The solution of spatiotemporal consistency is given from the space consistency, time consistency, spatiotemporal consistency and causality consistency. This scheme is successfully applied in the internal and external joint test system of certain type anti-air missile.