Abstract: The Fault Tree Analysis, which enjoys good logic and visualization features, is capable of showing the causes of production safety accidents by a logic tree to analyze the causes of accidents produced systematically, thus helps identify the key links in the production safety management. In this paper, the imagined personnel choking accident in spacecraft thermal vacuum test is analyzed by the FTA, including the basic events of accidents, the minimal cut sets, the minimal path sets and the coefficients of structural importance degrees. Based on the results, some recommendations of safety precautions are suggested.