Ceremonies are being held in Paris, London, Berlin as well as Washington. Moscow will hold its event on Saturday.
One of the first events was held at midnight in the Polish port of Gdansk, at the site where the first shots of the war were fired.
The commemoration in Gdansk was marked with a 21-gun salute on the stroke of midnight. Beams of light illuminated a monument to Polish defenders in Westerplatte and the national anthem was played.
In a speech, Poland’s President Bronislaw Komorowski said the war had started with the co-operation of two totalitarian regimes led by Hitler and Stalin, it ended with communism and the Iron Curtain, but ultimately brought integration of the region into the European Union.
Attended by UN Secretary General Ban Ki-moon and a number of leaders from eastern European countries, the commemoration began with a 21-gun salute in the city’s Westerplatte on the stroke of midnight.
Poland had organised the event as an alternative for those leaders who are boycotting Moscow’s Victory Parade because of ongoing tensions over Russia’s role in Ukraine’s conflict.
But most European leaders are attending events in their own country.
US Secretary of State John Kerry joined French President Francois Hollande and other dignitaries for the commemoration at Paris’s Arc de Triomphe, site of the Tomb of the Unknown Soldier.
President Hollande called VE Day a “victory of an ideal over a totalitarian ideology”.
Meanwhile, in Germany, parliament held a special session in which speakers paid tribute to both Western Allied forces and the Soviet Army who brought the war to an end.
Parliamentary Speaker Norbert Lammert called 8 May 70 years ago “a day of liberation” for Germans.
In London, a remembrance service will be held at the Cenotaph and 200 beacons will later be lit across the country.
In the US, a ceremony will be held at the national World War Two memorial in Washington followed by a flypast of vintage fighter planes.
It was on 8 May 1945 that Allied forces accepted the unconditional surrender of Nazi Germany, marking the end of the war in Europe. But it was not the end of WW2. It took another three months before Japan surrendered.