Disclosed is an aircraft avionics ground test system based on a PXI bus and Lab Windows Cvi. The system is composed of a hardware part and a software part, wherein their relationship is that the hardware part and the software part cooperate to achieve the functions of data acquiring, test result displaying, judging and recording. The hardware part is composed of a PXI test system, an adapter, an I/O module, an equipment cabinet, a test bench, a test cable and a power supply. The contents and procedures of the software part are as follows: firstly, a development environment is established and a test system application software engineering is established in the development environment; then, a test system software is designed according to time-driven task, event-driven task and background-run task; and finally, the design is initialized, service procedures are interrupted by a clock, and procedures are handled by an interface, wherein the whole operation process shows design in such aspects as software task division, task priority setting, task scheduling, communication between tasks, and display interface. The aircraft avionics ground test system provided by the invention has the advantages of modularization, integration and miniaturization in design.