Demidovsky (masculine), Demidovskaya (feminine), or Demidovskoye (neuter) may refer to: Demidovsky District, a district of Smolensk Oblast, Russia Demydivka Raion (Demidovsky District), a district of Rivne Oblast, Ukraine Demidovskoye Urban Settlement, an administrative division and a municipal formation which the town of Demidov and four rural localities in Demidovsky District of Smolensk Oblast, Russia are incorporated as Demidovsky (rural locality) (Demidovskaya, Demidovskoye), several rural localities in Russia