Shabdar Osyp (Mari: Шабда́р О́сып, 8 April 1898, Malaya Luzhala – 11 November 1937) was a Mari author.
He was born as Iosif Arkhipovich Shabdarov (Russian: Иóсиф Архи́пович Шабдáров) in the village of Izi Luzhalu in Mari El.
He started writing poetry in 1918. He studied at a pedagogical college in Kazan.
Like most of the Mari intelligentsia at the time, he became a victim of stalinism and was executed in Yoshkar-Ola on 11 November 1937. He was rehabilitated posthumously.