To provide a river water level monitoring support apparatus that can support monitoring of water level in a river, using a simple constitution.

In a river water level monitoring supporting apparatus 3, a water level observing apparatus 1 supports the monitoring of a wafer level in discharged rivers. The river water level monitoring supporting apparatus 3 comprises an observation result information receiving means T21 for receiving observation result information sent by the water level observing apparatus, a monitoring support information-generating means P21 for generating the monitor, at a position indicated by position information corresponding to the observation result information, based on the observation result information received by the observation result information-receiving means T21, and a monitoring support information output means P22 for outputting the monitoring support information generated by the monitoring support information generation means P21 to support the monitoring.