The Supreme Ruler of Russia, also referred to as the Supreme Leader of Russia, was the head of state and supreme commander-in-chief of the Russian State, an anti-Bolshevik government established by the White Movement during the Russian Civil War. For nearly two years from November 1918 until April 1920, the armies of the White Movement were nominally united under the administration of the Russian State, during which the Russian State claimed to be the sole legal government of Russia. The office's sole holder for most of its existence, and the only one to officially adopt the titles and functions of the Supreme Ruler, was Admiral Alexander Kolchak, who was elected to the position by the All-Russian Council of Ministers following the November 18 coup which overthrew the Directory.

The Russian State was a White Army anti-Bolshevik state proclaimed by the Act of the Ufa State Conference of September 23, 1918, “On the formation of the all-Russian supreme power” in the name of “restoring state unity and independence of Russia” affected by the revolutionary events of 1917, the October Revolution and the signing of the treaty of Brest-Litovsk with Germany.