Low-stress mechanical properties of spacer fabrics are investigated from the six polyester warp-knitted spacer fabrics and have been tested on Kawabata instrument. Three different types of spacer fabrics with a thickness of 2, 3.1 and 4 mm were prepared using three different face layer structures, namely locknit, rhombic mesh and hexagonal net and the influences on fabric properties were studied. The fabric with secured locknit structure and higher fabric thickness shows the high values in the compression, bending and shear properties. However, in case of tensile strength, the fabric of open mesh structure with higher fabric thickness decreases the tensile properties. The 3.1 mm fabric thickness along with hexagonal net structure shows the fine response on compression properties and reasonable effects on the other low-stress mechanical properties. © 2016, © The Textile Institute and Informa UK Ltd 2016.