To intake water without waste by an amount required for hydraulic power generation without deviating from the intake amount regulated by the laws on rivers.

This water intake structure 1 for taking in the water used for hydraulic power generation includes a first water channel 201 to which the water discharged from a water discharge port 101 provided to a water storage tank 100 in which the water from a river and the like is stored falls and which guides the fallen water to a hydraulic power generation facility and a second water channel 202 which is located at a position horizontally away further from the water discharge port 101 than the first water channel 201 to which the water discharged from the water discharge port 101 falls and which is positioned in parallel with the first water channel 201. More desirably, when the amount of water taken from the first water channel 201 is smaller than the target intake amount required for hydraulic power generation, the first water channel 201 and the second water channel 202 are configured so that the water discharged from the water discharge port 101 falls only to the first water channel 201, and when the amount of water taken from the first water channel 201 is equal to or larger than the target intake amount, these channels are configured so that extra water falls to the second water channel 202.