In order to fully tap the vast amount of the raw monitoring data in QAR, verify the reliability of ACARS messages and further assist the research in condition monitoring and fault diagnosis of aircraft and engine, the structure of the engine stable frame report has been researched and a method about extracting DFD report from its QAR data to meet the triggering conditions has been proposed, which have greatly enriched the engine performance monitoring data. The reliability of the method has been verified through computational analyzing both the actual ACARS reports and the extracted data of a B747-400 airplane. The result shows that this method has great prospects in engineering application.