The 83-year-old statue of "Lenin Speaking on the Top of an Armored Train," which dominated the square in front of the Finlyandsky, or Finland, Rail Terminal, was severely damaged in a blast by vandals April 1, 2009.
The blast -- which created a hole about 40 inches in diameter -- was first called a bad April Fools' Day joke but the Communist Party of the Russian Federation later described it as "a politically charged act of vandalism."
Party officials said the blast appeared to coincide with the anniversary of Lenin's April 3, 1917, arrival by train at that train station from Germany to start the Bolshevik Revolution, part of the Russian Revolution of 1917.
Police have not identified any suspects in the case nor made any arrests, RIA Novosti reported.
The statue was removed from the square in October and the hole was repaired at a cost of about $207,000, the agency said.
It is to be unveiled again April 20, on the eve of the 140th anniversary of the Bolshevik leader's April 22 birth.