National Unity Day was introduced by the Kremlin in 2005 to replace the communist holiday of November 7 celebrating the 1917 Bolshevik Revolution.
November 4 now marks liberation of Russia from Polish invaders in 1612.
Pro-Kremlin and opposition parties are going to hold their rallies and meetings across the country on National Unity Day.
Russian nationalists also plan to hold two marches in Moscow on November 4, the organizers of one of the marches earlier said.
The organizers said that the first "Russian March" would start at around noon, while the other is planned for 7:00 p.m. (4:00 p.m. GMT). Moscow authorities have sanctioned the marches, giving permission for gatherings of up to 7,000 people.
The first Russian March was held in Moscow on November 4, 2005. It was the first legally- sanctioned, large-scale nationalist event in post-Soviet Russia.
Last year's planned National Unity Day march by nationalist groups was banned by Moscow authorities. However, far-right groups defied the ruling and marched. Some 200 people were subsequently arrested.
