The Monument to Nicholas I is a bronze equestrian monument of Nicholas I of Russia on St Isaac's Square (in front of Saint Isaac's Cathedral) in Saint Petersburg, Russia. Unveiled on July 7th  [O.S. June 25th] 1859, the six-meter statue was a technical wonder of its time. It was the first equestrian statue in Europe with only two support points (the rear hooves of the horse), the only precedent being the 1852 equestrian statue of U.S President Andrew Jackson. 

The Neo-Baroque monument to the Russian ruler Nicholas I was designed by the French-born architect Auguste de Montferrand in 1856. When he planned the registration of Saint Isaac's Square, the uniform architectural ensembles of the Palace Square (in 1843) and the Senate Square had already been finished (in 1849). Monuments to the emperors Peter I and Alexander I dominated these squares. By tradition, de Montferrand intended to construct a monument on the new site, to unite the buildings of different architectural styles already there.

At the personal request of his successor Alexander II, Nicholas was represented as a prancing knight, "in the military outfit in which the late tsar was most majestic".Around the base are allegorical statues modelled on Nicholas I's daughters and personifying virtues. The statue faces Saint Isaac's Cathedral, with the horse's posterior turned to the Mariinsky Palace of Nicholas's daughter, Grand Duchess Maria Nikolayevna of Russia. This was said to have caused the Grand Duchess considerable discomfort.

The monument depicts Nicholas I, a determined absolutist Russian ruler, as a powerful military figure. However, being a junior army officer at heart, Nicholas I was especially devoted to his troops and was intricately involved in the details of the military — from ordering the alteration of military uniforms to specializing in the engineering of military fortresses. At the same time, his despotic regime (1825–1855) saw the crushing of the liberal Decembrist revolt and the November Uprising in Poland.

The monument also depicts the social activities of the emperor: Nicholas I was for many years the chief of the nearby Konnogvardejsky regiment. Elements of the city topography, the Konnogvardejsky parkway and Konnogvardejsky lane, and the Konnogvardejsky arena are combined with the Konnogvardejsky regiment uniform in which the emperor is dressed.