The invention discloses a spaceflight software critical resource accessing conflict detection method. After a morphology analysis unit conducts morphology analysis, a word label stream is recognized,after the morphology analysis unit conducts the morphology analysis according to the word label stream, a global variable table, a function table and a syntax tree are generated, after analysis is conducted through the syntax tree in combination with the global variable table, a global variable reading-writing relation attached table is obtained, after the analysis is conducted in combination withthe function table, a function reading-writing relation attached table and a function calling relation table are obtained, after a thread inlet is recognized according to the function calling relation, thread coloring is conducted on the function calling relation table, finally through the combination of the global variable reading-writing relation attached table, the function reading-writing relation attached table and the function calling relation table after being subjected to thread coloring, analysis and examination are conducted to obtain the global variable reading-writing conflict situation and the writing-writing conflict situation. By means of the spaceflight software critical resource accessing conflict detection method, a corresponding critical resource accessing conflict examination tool can be developed, the situation of critical resource accessing conflict in software is quickly and accurately recognized, and thus the software reliability is improved.