With the development of green prefabricated rural building in decades, the traditional cold-formed steel (CFS) wall reveals some shortcomings, such as poor sound insulation, low bearing capacity and weak thermal insulation. In order to improve the performance of walls and the degree of assembly, a novel type of prefabricated light mortar-filled CFS composite walls was developed. A total of six composite walls were tested under axial loading. The failure modes, load-displacement relations, load-strain relations, bearing capacities were studied comprehensively. The parameters including sheathing, filling type, wall thickness, and the number of steel mesh layers were studied. The test results showed that the sheathing, filling type and the thickness of wall panel had great effect on the performance of composite wall panels under axial compression. The number of steel mesh layers appeared no obvious influence on the bearing capacity. Additionally, the calculation method of bearing capacity of the wall panels under axial compression was proposed, and its accuracy was verified by experimental data.