To provide a dust removal method for a screen of a waterway for power generation that can remove dirt deposited on the screen without letting an operator go to the place where the screen is installed.

The dust removal method for the screen of the waterway for power generation is a dust removal method for a screen 3 of a waterway 2 for power generation which includes: an intake waterway system 2a connecting a water supply source to hydraulic power generation facilities 1; a surplus waterway system 2b which branches off from the intake waterway system 2a and discharge surplus water when the water level of the intake waterway system 2a becomes higher than a predetermined water level, the screen 3 being arranged downstream from a branching position of the surplus waterway system 2b of the intake waterway system 2. When the water level of the intake waterway system 2a upstream from the screen 3 is higher than the water level downstream from the screen 3, the output of a power generator 10 is lowered at least once.