To provide a fluidization treatment method of construction emission which is applied to waste having a large water content such as muddy water, whereby a composite having an appropriate flow property can be produced without causing material separation and can keep facility cost low because there is no need of a truck mixer or a pumping system at construction.

The fluidization treatment of the construction emission is performed by producing the composite by mixing the construction emission containing a large amount of water such as muddy water and sludge with a solidification material, spherodized incinerated ash, coal ash and slag which is pulverized into a grain size of ≤2.5 mm in appropriate proportions.