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• Multilayer coating consisting of HfC–Hf 6 Ta 2 O 17 and HfC–SiC sublayers was made on SLE C/C composites using SAPS. • The multilayer coating showed better ablation resistance than monolayered coatings as being exposed to the oxyacetylene torch. • Microstructural analysis indicated less cracks formed in the multilayer coating as compared to the monolayered coatings. • Finite element model demonstrated the lower thermal stress of multilayer coating. Carbon/carbon (C/C) composites have been acknowledged as potential candidates in aerospace vehicles, but their oxygen sensitivity still remains an enormous challenge. In this work, a novel multilayer coating consisted of HfC-2.5 mol.% Hf 6 Ta 2 O 17 , HfC-40 mol.% SiC, HfC-2.5 mol.% Hf 6 Ta 2 O 17 and HfC-60 mol.% SiC sublayers from surface to inside was designed and fabricated on the surface of C/C composites with sharp leading edge by plasma spraying. Its ablation resistance was assessed using oxyacetylene torch with a maximum temperature over 2300 °C and compared with monolayered coatings. The multilayer coating revealed preferable ablation retardation capacity evidenced by its integrated profile and less flaw quantity. Such benefits were primarily stemmed from the effective structural design and rational material selection. The former was able to reduce the thermal stress within the ablated scale, the latter contributed to rising the high-temperature resistance and oxygen barrier ability of the coating. [Display omitted] [ABSTRACT FROM AUTHOR]