Igor Platonovich Demidov (Russian: Игорь Платонович Демидов; 5 June 1873 - October 20 1946) was a Russian politician.
A cadet then a member of the State Duma, he went into exile in Paris after the Bolshevik Revolution. He was a member of the editorial staff of the newspaper "Последние новости" ("News"), then its assistant chief editor, and in the early 1920s was also a member of the parish council of St Alexander Nevsky in Paris.