Kozmodemyansk () is the name of several inhabited localities in Russia.
Urban localities Kozmodemyansk, Mari El Republic, a town in the Mari El Republic;
Rural localities Kozmodemyansk, Sovetsky District, Mari El Republic, a village in Mikhaylovsky Rural Okrug of Sovetsky District in the Mari El Republic; Kozmodemyansk, Perm Krai, a selo in Karagaysky District of Perm Krai Kozmodemyansk (selo), Yaroslavl Oblast, a selo in Melenkovsky Rural Okrug of Yaroslavsky District in Yaroslavl Oblast Kozmodemyansk (settlement), Yaroslavl Oblast, a settlement in Melenkovsky Rural Okrug of Yaroslavsky District in Yaroslavl Oblast