Kozelsky (masculine), Kozelskaya (feminine), or Kozelskoye (neuter) may refer to:
Geography Kozelsky District, a district of Kaluga Oblast, Russia Kozelsky (rural locality) (Kozelskaya, Kozelskoye), name of several rural localities in Russia Kozelsky (volcano), a volcano on Kamchatka Peninsula
People Arno Kozelsky (b. 1981), Austrian soccer player Kozelsky (family), a princely family of Rurikid stock
Other 8229 Kozelský, a main belt asteroid