To provide a recycling method of polymer sludge water which has to be disposed of by an industrial waste disposal method by simply separating earth and sand.

The earth and sand is hardly separated from the polymer sludge water, thereby the application field of the polymer sludge is limited. However, the application of a special enzyme decomposes the polymer almost instantly, reduces the viscosity, and facilitates the separation of earth and sand. The earth and sand can be disposed and recycled as drained/surplus soil. The separated water is used for arrangement water for chemical injection or the like in the same way as ordinary water, thus both the water and the earth and sand are recycled.