This invention relates to a corrosion-resistance and blocking-resistance supercritical water oxidation reactor. It is composed of: a casing, a water inlet, a jacketed supporting ring and a spring ring, an annular water entrance and a water dash plate, inner cylinder of the reactor, raw material feeder, nozzle, an outlet of reactant and multi-point optical fiber online thermo-detector. In said reactor, there are a process water jacket area, supercritical water oxidation area, a sub-critical water area for dissolving inorganic salts on the bottom of the inner cylinder of the reactor. The process water jacket area is divided into two or more than two layer area by the supporting ring and the spring ring. The water, after removing oxygen and removing salts, passes through porous-wall structure enters the reaction area and forming a protective water membrance over the inner wall of the reactor. The temperature sensor and optical fiber are placed in a sleeve which is placed near the central line of the reactor. Advantages are: easy to be maintained, safety operation.