Flight control system is one of the most highly complex critical control system on civil aircraft, the fly-by-wire flight control system have an advanced aircraft control performance, but at the same time, is more sensitive to electromagnetic interference, such as HIRF (High Intensity Radiated Field) and IEL (Indirect Effect of Lightning). The fly-by-wire flight control system level integrated HIRF/L test design and verification method is studied. The necessity and the critical design program of the test are introduced, and the specific design method of general consideration, system architecture, test items, rig installation, pass/fail criteria are proposed and studied. The conformity test results show that the proposed design can meet the requirement of the airworthiness regulation and can provide a positive reference for the integrated system level EMC test engineering technical solution of other civil aircraft critical control system verification.