To provide a rainwater storage utilization facility conducting a drainage adjustment and feeding the rainwater stored in a storage section as domestic water or the like for effective utilization.

This rainwater storage utilization facility is provided with the concrete storage section 1 formed into a hollow box shape opened on the upper face, a cover body 2 closing the upper face of the storage section 1, an inflow path 3 through which rainwater flows into the storage section 1, an openable drain port 4 through which the rainwater stored in the storage section 1 flows out, an overflow type discharge port 5 through which the rainwater in the storage section flows out when its water level reaches a fixed value or above, and a rainwater utilization device 6 pumping up the rainwater in the storage section with a pump for distribution.