At present, the demand for structural thermal test of aerospace products is increasing, but the cost of structural thermal test is high, the risk is high, and the current thermal test methods are difficult to solve the drawbacks and difficulties. This requires the thermal test to have a higher technical ability to match the development of new aerospace products. In recent years, due to the rapid development of CAE technology, virtual test technology has become a new means to verify product thermal control design. This paper briefly describes the design approach of virtual test system for structural thermal test by digital modeling each link of the ground structure thermal test. Each module of the system forms a closed loop system, which is used for virtual simulation of the whole process of structural thermal test. The establishment of virtual test system for structural thermal test can predict and guide structural thermal test. Virtual test and simulation verification have become the main ways to shorten the development period, reduce the project risk and development cost. Through the combination of simulation and virtual test with other test methods, the whole system performance test can be carried out effectively.