To provide a stirring device for reutilizing a ready-mixed concrete waste water, which is capable of supplying a mixed solution having a prescribed concentration to the ready-mixed concrete producing device to secure the excellent quality of the ready-mixed concrete and at the same time, to effectively reutilize the ready-mixed concrete waste water at most by uniformalizing the concentration of the mixed solution in a stirring vessel.

The stirring device for reutilizing the ready-mixed concrete waste water has the stirring vessel 1 and an agitation blade 4 for stirring the inside of the stirring vessel 1 and is for stirring a mixture of the ready-mixed concrete waste water with a new water by the agitation blade 4 and an ascending flow forming member 3 extending in the up-and-down direction is mounted on the inner peripheral surface of the stirring vessel 1. The ascending flow forming member 3 can be mounted on the plural position at an equal interval in the peripheral direction of the inner peripheral surface of the stirring vessel 1.