Ni-NCNT/AC catalyst support was prepared by in-situ synthesis of Ni single atom confined Ni-NCNT carbon nanotubes on the surface of activated carbon, and Ruthenium catalysts loaded on these support was prepared by impregnation method and degrade acetic acid wastewater.The morphology, structure, element valence, surface adsorption and chemical properties of the samples were analyzed and density functional theory(DFT) calculated by scanning electron microscope(SEM), transmission electron microscopy(TEM), X-ray absorption spectrum(XAFS), X-ray electron energy spectra(XPS),temperature-programmed reduction(H2-TPR) and Carbon monoxide diffuse reflectance infrared Fourier transform spectroscopy(CO-DRIFTS).The results show that Ni single atom as a catalytic promoter can promote the surface precious metals to play a higher catalytic activity for the oxidation of acetic acid by changing the electronic properties of the substrate material.Under the conditions of temperature 250℃, pressure 6.5MPa and continuous operation for 10 days, the removal rate of acetic acid remained stable at more than 95%, and the catalyst had high activity and good stability.