In order to analyse the deformation mechanism and force distribution of spacer fabrics during compression progress, it is established that the loop structural model of weft-knitted spacer fabric with spacer filaments arranged in X-shape by Rhino software in this paper, and the flat plate compression behaviour of the spacer fabrics was simulated by finite element method in Abaqus software. By combining the experimental and finite element simulation, the stress distribution and change trend on the fabric were analysed when the compression amount was 5%, 20%, 35%, 50%, 65% and 80%, to investigate the failure mode of WKSFs under flat plate compression, and to achieve the progressive damage analysis of the surface layer and spacer layer yarns in the process of compression.The simulated curves of the stress-strain were consistent with the experimental results, which indicated that the model was able to reveal the compressor mechanism of the WKSFs,and provides a basis for optimising the structural design and mechanical properties of weft-knitted spacer fabrics.