Mg-Al-Fe ternary layered double hydroxides (LDH) were synthesized based on red mud (RM) by calcination-rehydration method, and characterized using X-ray diffraction (XRD). And, the LDH coated with ZnSn(OH)6 (ZHS) was studied by XRD, scanning electron microscopy (SEM), transmission electron microscopy, and energy dispersive spectroscopy (EDS). The flame retardant and thermal properties of EVA composites based on RM, LDH and LDH coated with ZHS were studied using cone calorimeter test (CCT) and thermogravimetric analysis (TGA). The CCT data indicates that heat release rates (HRR) of EVA with LDH coated with ZHS decreases in comparison with that of EVA, EVA/RM and EVA/LDH composites. The TGA data show that LDH coated with ZHS can apparently increase the thermal stability and the charred residues after burning. POLYM. ENG. SCI., 54:2918–2924, 2014. © 2014 Society of Plastics Engineers