Short contact time liquefaction of subbituminous Taiheiyo coal by using binary system vehicles at 400°C for 10 minutes under autogenous condition was studied. These vehicles were mainly quinoline + 1, 2, 3, 4-tetrahydroquinoline (THQ), anthrathene oil THQ, petroleum vacuum residue pitch (VR-Pitch) + THQ, tetralin + THQ.On the coal liquefaction, THQ has a noticeable effect as a hydrogen donor vehicle for coals under d. a. f. C % 80. And petroleum vacuum residue is also very important hydrogen donor source for Solvolysis liquefaction of coal.In the case of mixtures of hydrogen non-donor and THQ, the conversion to benzene soluble matter (BS) increased with increase of THQ content and approached to that (84.5%) by THQ only.In the case of mixtures of hydrogen donor and THQ, especially VR-Pitch and THQ, the large conversion to BS more than 84.5% (THQ only) was obtained in the range of 10 to 40 wt% content of VR-Pitch. The conversion to BS was nearly 100% with a mixture of 30 wt% VR-Pitch and 70 wt% THQ.However, in the mixtures of hydrogen donor vehicles such as tetralin, hydrogenated anthrathene oil and THQ respectively, the conversion to BS was not enhanced among various mixing ratios.