PURPOSE: To carry out filtration of a sufficiently large amount of water for a long duration by providing a hollow main body, a water supplying inlet, a hollow rotary body, a rotary body driving apparatus, a passing hole of the rotary body, a filter layer of the passing hole, and a water discharging outlet.

CONSTITUTION: In a filtration apparatus 1, water to be filtered is supplied to a rotary body 5 through a supplying inlet 3, flows to outside from inside of the rotary body 5 while passing a filter layer 27, and is discharged through a passing hole 23 of the rotary body 5. When the water passes the filter layer 27, due to the rotation of the rotary body 5 by a turbine 29 which utilizes water flow from the supplying inlet 13, centrifugal force is applied to water to run forcedly toward outside. Consequently, since water passes the filter layer 27 uniformly while being filtered, possibility that impurities converge unevenly on a part and that choking occurs is lowered and even if choking occurs, a proper amount of water passes by the forcing centrifugal force and thus it is no need to clean or replace the filter layer 27 frequently.