In this work, layer-by-layer assembly technique has been employed to deposit cationic chitosan (CH) and anionic montmorillonite (MMT-Na ? ) polyelectrolyte coatings on polyamide 6 (PA6). Without an additional surface treatment, 5, 10 and 20 bilayers of CH/MMT-Na ? were successfully adsorbed on PA6 matrix as confirmed by XRD, ATR-FTIR and SEM-EDX results. The thermal stability was evaluated using TGA and DSC methods, and it was found that neat PA6 demonstrated better performance (by ca. 5°C) and bilayers caused slightly delayed melting of PA6 crystalline phase. Some interesting results proving imparted flame retardancy by applied assemblies were obtained by vertical (VFT) and horizontal (HFT) flammability tests and microcalorimetric analysis (MCC) methods. It was found that all of the coated PA6 specimens have accomplished V-0 notes in VFT and the intensity of melt dripping reduced. According to MCC results, PA6 covered with 20 bilayers showed the highest reduction-up to 10% relative to reference material-in PHRR.