In the design process of avionics system for civil aircraft, the system integration is beginning with each item. Test Ready Review (TRR) will have to be carried out in order to keep the test system in control, also to satisfy accuracy and traceability of system integration and test. Based on the introduction of Test Readiness Review, this article gives a description of TRR key points from the system under test, test documents, test environment, test records, quality audit, configuration control, compliance with the development plan combined ARP4754 and actual project case. Analysis results have been applied in practice and show that it is effective and reasonable.