Use first dipping adsorption with KBH4 reduction method of the preparation of 5%Ru/C catalysts which have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (TEM). Results show that dispersion degree of 5%Ru/C catalyst is high, the average grain size of metal ruthenium 2 ~ 3 nm. In quinoline hydrogenation reaction, the catalyst showed high catalytic activity. With water as solvent,, at 100 ℃, reaction 1 h ,2 MPa hydrogen pressure, the conversion of quinoline was 100% and the selectivity of 1, 2, 3, 4 -tetraquinoline was up to 100%,TOF for 338h-1 .