Abstract: The present invention relates to a method and a device for enclosed recycling of oil-water-sludge in an oil shale dry distillation system, comprising: scrubbing and condensing oil shale dry distillation gas at a gathering pipe section, a gas tower section, an air tower section, and a cooling tower section respectively to recycle shale oil section by section; using a separator at an outlet of each section to purify and collect the shale oil, while purifying and recycling scrubbing/cooling water; using multistage dedusters to remove oil sludge entrained in an oil-water product; using an oil sludge collecting tank and a filter after the deduster to concentrate and recycle an oil sludge; and using cyclones before and after the gas tower section to remove aerosol particles and water drops entrained in circulatory gas.