To provide a fluid stirring apparatus capable of causing a sufficient mixing and stirring effect in a stirring tank by changing the releasing energy of water current generated by upper and lower stirring blades and the releasing direction observed in a plane view by using respectively operation-controllable rotating motors for the upper and lower stirring blades.

The fluid stirring apparatus 10 comprises a lower stirring mechanism 13 installed in a stabilization liquid production tank 11 and having a lower stirring blade 19 and a lower rotating motor 18 for rotating the lower stirring blade 19 and an upper stirring mechanism 14 installed above the lower stirring mechanism 13 in the stabilization liquid production tank 11 and having an upper stirring blade 32 and an upper rotating motor 31 for rotating the upper stirring blade 32, and the rotating motor 18 of the lower stirring mechanism 13 and the rotating motor 31 of the upper stirring mechanism 14 are made respectively independently controllable for operation.