According to the test requirements of C919 AFDX aircraft avionics bus，a data acquisition device based on FPGA is designed, which realized the 100% raw data forwarding and realtime analysis function of AFDX avionics bus. This paper mainly describes the plan for AFDX bus acquisition and detailed introduces the design of AFDX acquisition equipment’s hardware and software. Which conduct The simulation test and the avionics laboratory test, the results indicated that the acquisition module has no effect on airborne AFDX bus, and which is correct. In the end, AFDX acquisition module is stable, reliable, and can meet the test requirements of AFDX bus data.