Rayakoski (Russian: Раякоски; Finnish: Jäniskoski) is an inhabited locality in Pechengsky District of Murmansk Oblast, Russia, located adjacent to the tripoint between Finland, Norway, and Russia.
Rayakoski is located around the Rayakoski Hydroelectric Power Plant, built in 1956.
Rayakoski and its hydroelectric plant were sold by Finland to the Soviet Union in 1947, in exchange for German investments in Finland confiscated by the Soviets.