Putin has repeatedly likened the war in Ukraine - which he casts as a defensive move against a West which wants to carve up Russia - to the challenge Moscow faced when Adolf Hitler invaded the Soviet Union in 1941.
"The decisive battles for the fate of our Motherland have always become patriotic, all-national and sacred," the 70-year-old president told veterans and soldiers assembled on Red Square for the annual Victory Day parade.
"A real war has again been unleashed against our homeland," he said.
Putin hailed Russian forces in Ukraine as heroes who were fighting for the country's future against a West which, he said, had forgotten the decisive role played by the Soviet Union in defeating Nazi Germany.
"The whole country rallied to support our heroes. Everyone is ready to help, praying for you," he said of those taking part in what the Kremlin calls a "special military operation."
Putin cheered for "Russia, for our valiant Armed Forces, for victory!"
Cheers rang out across Red Square, with a gun salute and the Russian national anthem, though with a much-curtailed show of military hardware - and no aviation. A single tank took part - a T-34, a type used in World War Two.
This anniversary falls less than a week after Russia accused Ukraine of attacking the Kremlin citadel with two drones in an attempt to kill Putin. Kyiv has denied any involvement.
In his speech, Putin said "Western globalist elites" were sowing Russophobia, while the Ukrainian people had become "hostages to a state coup" and to the ambitions of the West.
However Putin also paid tribute to the armies of the United States, Britain and others which had fought the Nazis, and also to China's fight against the Japanese.
The Soviet Union lost 27 million people in World War Two, including many millions in Ukraine, but eventually pushed Nazi forces back to Berlin, where Hitler committed suicide and the red Soviet Victory Banner was raised over the Reichstag in 1945.
Kyiv and its allies accuse Putin of waging an unprovoked war of aggression in Ukraine to seize land. They deny Putin's claim that the expansion of the Nato alliance to Russia's borders poses a threat to its security or justifies Moscow's invasion.
As many as 354,000 Russian and Ukrainian soldiers have been killed or injured in the Ukraine war, which is now in its 15th month and could well grind on well beyond 2023, according to a trove of purported US intelligence documents posted online.
Reuters