NOVELTY - A muddy water degradation intermittent reactor of Naididae-animalcule cogeneration system comprises mud reduction reactor connected with sewage degradation reactor through water inlet and mud regurgitant pipeline; air inlets located above the mud reduction reactor and sewage degradation reactor; exposure devices arranged under the mud reduction reactor; water outlet disposed at sewage degradation reactor; water inlet; elastic materials attached with Naididae; active mud containing animalcule bacteria groups placed in sewage degradation reactor; and stirrer.    USE - A muddy water degradation intermittent reactor of Naididae-animalcule cogeneration system used for treating mud-containing water (claimed).    ADVANTAGE - After sewage treatment, the remaining mud generated amount is less than 0.12 kg suspended solid/kg biological oxygen demand. The mud reduction rate is greater than 60%.    DETAILED DESCRIPTION - A muddy water degradation intermittent reactor of Naididae-animalcule cogeneration system comprises mud reduction reactor connected with sewage degradation reactor through water inlet and mud regurgitant pipeline; air inlets located above the mud reduction reactor and sewage degradation reactor; exposure devices arranged under the mud reduction reactor and sewage degradation reactor inside; water outlet disposed at upper section of sewage degradation reactor; water inlet provided at upper section of mud reduction reactor; elastic materials uniformly distributed in mud reduction reactor and attached with Naididae; active mud containing animalcule bacteria groups placed in sewage degradation reactor; and stirrer provided with decanter close to water outlet. The mud regurgitant pipeline is connected between mud reduction reactor and sewage degradation reactor in regurgitant manner. An INDEPENDENT CLAIM is included for method of using muddy water degradation intermittent reactor of Naididae-animalcule cogeneration system, comprising feeding sewage containing mud into mud reduction reactor from first water inlet, where mud of sewage degradation reactor enters into mud reduction reactor through mud regurgitant pipeline, and is eaten by Naididae to degrade; introducing sewage with reduced mud into sewage degradation reactor through water inlet, where organic pollutant, nitrogen and phosphorus in sewage are degraded by animalcule in active mud; and filtering outlet water by decanter and discharging through water outlet.