For the structural strength test of multi-wheel multi-pillar landing gear structure aircraft, the landing gear load is difficult due to the narrow loading space of the landing gear. So a differential loading method was proposed. A loading force bar was formed by designing the lever to be actuated between two adjacent landing gears, which could meet the application requirement of the two-way alternating load of all the landing gears. The method was installed in place at one time, and the space occupancy rate was low, which greatly reduced the test dressing period. The application of the differential loading method on the multiwheel multipillar landing gear was simulated by software simulation, and the method had been successfully applied to the fullmachine fatigue test of a certain type of aircraft. The simulation and application results show that the differential loading method can fully realize the application of the two-wheel alternating load of the multi-wheel multi-pillar landing gear, which provides reference for the assessment of multistructure test pieces in similar complex areas.