To provide a lightweight turbid water treatment apparatus can be transported and installed in a state that a filtration tank is filled with a filter medium, can carry out automatic filtration and automatic back-washing, reduced in maintenance, and can highly precisely filter turbid water generated in a construction work field.

A water supply and discharge chamber 3 equipped with a water supply and discharge tube 2 is installed in an inner lower part of a filtration tank 1, and a supply side of the water supply and discharge tube 2 is connected to a pipe p4 for supplying treated water of a treated water control tank T1 to the water supply and discharge chamber 3 via a check valve V1. A discharge side of the water supply and discharge tube 2 is connected to a pipe p2 for discharging treated water of the water supply and discharge chamber 3 to the treated water control tank T1 via an automatic adjustment check valve V2. A filter medium 4 is set in an upper part of the water supply and discharge chamber 3, and the filter medium 4 is formed by layering a granular filter material 4b on an upper part of silicic sand 4a. A rotary rake 8 installed above the filter medium 4 includes a plurality of stirring claws 10 arranged in a comb-like state in right and left horizontal arms 9a and 9b of a rotary shaft 8a.