Veterans, most of whom are more than 90 years old, were VIP guests at a civic lunch in Belfast City Hall.
Japan formally surrendered on board the USS Missouri in Tokyo Bay on 2 September, 1945, bringing an end to the conflict.
Veterans attending the lunch were each given a commemorative medallion as a keepsake.
Alfie Martin, 95, who won the Distinguished Flying Cross for bravery, was among the guests.
"This is a very nice gesture by Belfast City Council, and one which is very much appreciated," he said.
"It was a very nostalgic event for all of us."
Belfast's deputy lord mayor Guy Spence, said: "It was a real honour to host this commemorative luncheon and to acknowledge the incredible contribution these veterans have made.
"This anniversary is particularly poignant given the ages of the veterans who are able to be with us and be part of such an important commemoration.
"We owe them a great deal.
"It is a privilege to pay tribute to those who made enormous sacrifices and showed incredible bravery to protect our freedom," he added.
The 70th anniversary of the end of World War Two has been marked in Belfast.