To control a water intake amount when taking water from a river, a pond or a lake.

The present invention is a water intake structure which comprises: a water storage section 10 where water to be an intake source is stored; a flow channel 20 to introduce the water to an intake side; a floating gate 30 which has a water storage structure and is supported so as to be movable in a vertical direction depending on a relation between a self-weight and a buoyancy of the water running in the flow channel; and a headrace structure to introduce the water in the water storage section 10 into the water storage structure when a water level in the water storage section 10 exceeds a prescribed level. Additionally, the water intake structure has a water circulation structure which runs the water stored in a water storage space 32 into the water storage section 10 by automatically communicating the water storage space 32 with the water storage section 10 when the water level of the water stored in the water storage section 10 is lower than the water level of the water stored in the water storage space 32 and the floating gate 30 sinks in the water running in the flow channel 20 lower than a prescribed depth.